Fermi Questions

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Volume 36 • 1 September 2004

Magazine of the Science Teachers’ Association of Ontario

FEATURING: Improving Scientific Literacy Using Fermi Questions Emerging from the Chrysalis Careers in Science: Neonatal Nurse Growing with your Students New Science and Tech Website for Students Physics is Bananas! Weather on the Web Follow that Worm! Learning by Accident STAO Membership Report

LOOK UP... WAY UP: CANADIAN ASTRONOMER GETS RARE VIEW OF THE UNIVERSE PAGE 15

ELEMENTS: Aircraft Lift

CHECK OUT STAO/APSO’S BRAND NEW LOOK!

Greening the Way Ontario Learns

VISIT US ON THE WEB AT http://www.stao.org

Goggled Science

Keep current with the latest updates in Science Education.

STAO/APSO 2004 Managing Change for Successful Learning

November 11-13, 2004 Featuring a variety of fabulous featured peakers and incredible topics!

Jack Bacon – On the Lunar Mars Push and History in the Making Philip Currie – The Dinosaurs of Canada: Scientific, Cultural and Educational Icons Jay Ingram – Grabbing their Attention: Why Not Use the Science of Everyday Life? Bob McDonald – In the Pit, On the Peak: The highs and lows of Canadian Science Joe Schwarcz – Science & the Paranormal and To Eat or Not to Eat... that is the Question Ivan Semeniuk – Seven worlds in Seven Days ...plus over 200 other speakers!!! DAILY SPECIAL EVENTS:

STAO/APSO Mixer and the banquet on Thursday STAO/APSO Celebration Luncheon on Saturday STAO/APSO AGM on Friday

Register early and save on your registration fees! See www.stao.org for full details and watch for your conference planner in the mail!

Doubletree International Plaza Hotel 655 Dixon Road • Toronto, Ontario • Canada M9W 1J3 Hotel Reservations: 416-244-1711 or 1-800-668-3656 Reserve before October 10th to receive the special STAO2004 conference rates.

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CONTENTS

TAOCOM MEMBERS

Ray Clement, Chair Ministry of Environment 125 Resources Road Etobicoke, ON; M9P 3V6 (416) 235-5906 FAX (416) 235-5744 [email protected]

CRUCIBLE/ELEMENTS EDITOR/ Brenda Kosky Brenda Kosky Communications Inc. 38 Golfview Drive Dundas, Ontario; L9H 6V3 (905) 627-9538 FAX (905) 627-9531 [email protected] ADVERTISING MANAGER Terry Price (905) 939-8104 [email protected] ASSOCIATE EDITORS Jim Agban 295 Bud Gregory Blvd Mississauga, ON; L4Z 2R4 (905) 890-3450; FAX (905) 501-1161 [email protected] Don Galbraith 360 Ridelle Ave. #915 Toronto, ON; M6B 1K1 (416) 978-7870 [email protected] Herman Proper Ontario Alliance Of Christian Schools 617 Garner Road East Ancaster, ON; L9G 3K9 (905) 648-2100; FAX (905) 648-2110 [email protected]

DISCLAIMER

Malisa Mezenberg Currently on secondement to OECTA Provincial Office (416) 367-8033 [email protected] Laurel Schollen School of Biological Sciences and Applied Chemistry, Seneca College Seneca @ York Campus 70 The Pond Road Toronto, ON; M3J 3M6 (416) 491-5050, ext. 3775; FAX (416) 661-3936 [email protected] Sandy Szeto Windfields Junior High School 375 Banbury Road North York, ON; M2L 2V2 (416) 395-3100 FAX (416) 395-3105 [email protected] Derek Totten W.J. Watson P.S. 162 Carrick Ave. Keswick, ON; L4P 3P2 (905) 476-1618 FAX (905) 476-5340 [email protected]

President’s Message ........................................................5 Improving Scientific Literacy Using Fermi Questions ....7 Emerging from the Chrysalis: 10 Tips for First Year Teachers ..........................................................10 The Hardy Weinberg Equilibrium and Chi-Square Test of Significance: Part II – Practice Questions..............12 Careers in Science: Neonatal Nurse Nancy Yeh............13 Canadian Astronomer gets Rare View of the Universe ......................................15 NASA Brain Bites Provide Answers for Curious Minds..........................................................17 Growing with Your Students ..........................................18 Just for Fun from the STAO/APSO Virtual Library ........23 NRC Launches New Science and Tech Website for Students ..................................................................24 Fun with Pennies ............................................................25 Physics is Bananas ........................................................27 Weather on the Web: From Observations to Explanations ........................................................28 STAO Hot Website: Rubistar is for you! ........................29

EXECUTIVE LIAISON John Henry 111 Bunker Hill Drive Hamilton, ON; L8K 5X3 (905) 560-9594; FAX (905) 560-9594 [email protected] PRODUCTION MGR./ASST. EDITOR Shayla Gunter-Goldstein Brenda Kosky Communications Inc. (416) 445-9538; FAX (416) 445-6695 [email protected]

Follow that Worm! ..........................................................30 Learning by Accident......................................................33 Safety Q & A ..................................................................34 Elements....................................................................Insert

ON THE COVER 140-Foot Telescope. The NRAO 140 Foot Telescope was completed in the spring of 1965. Located in Green Bank, West Virginia. Used with permission. National Radio Astronomy Observatory, a National Science Foundation Facility, managed by Associated Universities. Inc.

Crucible is printed on recycled paper.

The enclosed information is to be considered as suggestions and recommendations only, and is neither to be considered as legal requirements nor as the policy of the Science Teachers’ Association of Ontario. The conclusions, findings and opinions expressed herein are those of the individual contributors and not of the Science Teachers’ Association of Ontario. Neither the Science Teachers’ Association of Ontario nor the individual contributors may make any guarantee, warranty or representation as to the correctness or sufficiency of any of the information herein. It can neither be assured that all necessary warnings and precautionary measures are contained herein, nor that additional information or measures may not be required due to particular exceptional circumstances, or because of local present, new or modified legislation in any region where the enclosed information is followed. Neither the Science Teachers’ Association of Ontario nor the individual contributors on behalf of themselves, their agents, subcommittees or anyone acting on their behalf assume any responsibility for any of the material published herein, and both the Science Teachers’ Association of Ontario and the contributors disclaim any liability in negligence or otherwise for any injury, loss or damage of whatever nature resulting from the use of any of the material herein. Crucible is published five times a year by the Science Teachers’ Association of Ontario. Issue dates are September, November, January, March, and June. ISSN 0381-8047. Canada Post Canadian Publications Mail Sales Product Agreement #491314. Undelivered issues should be returned to: STAO Membership Office, The Science Teachers’ Association of Ontario, Box 771, Dresden, Ontario N0P 1M0 Individual membership in STAO includes a subscription to both Crucible and Elements. For membership rates please turn to page 39. Send cheque or money order to STAO Membership Office, The Science Teachers’ Association of Ontario, Box 771, Dresden, Ontario N0P 1M0. Change of address should be made to the preceding address at least six weeks prior to moving in writing, by telephone at 1-800-461-2264 or by fax at 519-683-2473. All rights reserved. Articles may be reproduced, but requests for permission should be made directly to the author. The author’s address will be supplied by the Editor if it does not appear with the article. Crucible welcomes both readers’ comments and articles. Articles should be typewritten clearly or word processed. Submissions on CDs or by email would be greatly appreciated. Articles should not be more than 2 500 words long. Include with articles approximately 25 words of the author’s biography AS WELL AS the grade level for which the information may be useful. We also invite head-and-shoulders, black-and-white authors’ photographs, as well as other photographs which would complement the contents of the submissions. If articles are accepted for publication, we reserve the right to make appropriate editorial changes in style and length. Please send all correspondence to Shayla Gunter-Goldstein, Assistant Editor, Crucible magazine, c/o Ste. 307, 8 Roanoke Rd., North York, Ontario, M3A 1E6. Email: [email protected]. Writers should supply full name, school address, and home and school telephone numbers.

September 2004

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STAO BOARD OF DIRECTORS: 2004 - 2005 1ST VICE PRESIDENT Chuck Cohen (905) 787-8772, xt. 615; [email protected]

SECRETARY Joanne Harris (905) 877-6976 [email protected]

SCCAO REPRESENTATIVE Xavier Fazio (905) 632-6314 x.214 [email protected]

PRESIDENT John Henry (905) 560-9594 [email protected]

2ND VICE PRESIDENT Stephanie Grant [email protected]

REGIONAL DIRECTOR Wuchow Than (905) 627-7049 [email protected]

PAST-PRESIDENT Maurice Di Giuseppe (416) 483-0591 [email protected]

TREASURER Dr. Greg Finn (905) 688-5550 x.3528; [email protected]

PROFESSIONAL DEVELOPMENT COORDINATOR Malisa Mezenberg (416) 367-8033 [email protected]

Executive Committee

MEMBER AT LARGE Vacant

Regional Councillors REGION 1: THE NORTHERN REGION Susan Robinson (807) 345-1461 [email protected]

MEMBERSHIP Cheryl Madeira (416) 393-5561 [email protected]

REGION 2: THE WESTERN REGION Vacant

ELEMENTARY CURRICULUM Derek Totten (905) 476-1618 [email protected]

REGION 3: THE CENTRAL REGION Vacant REGION 4: THE EASTERN REGION Dennis Paré (613) 821-2261 [email protected] REGION 5: METRO TORONTO REGION Julie Vander Meij [email protected]

SECONDARY CURRICULUM Milan Sanader [email protected] SAFETY Dr. Ralph Chou (519) 888-4567, xt. 3741 [email protected] INTERNAL RELATIONS Dr. Gino Ferri (519) 364-4433 [email protected]

STAOCOM Ray Clement See page 3: STAOCom Listings EXTERNAL RELATIONS Naomi Epstein (416) 484-7229 [email protected]

Committee Chairs CONFERENCE CO-CHAIR 2005 Adrian yu Lee [email protected] SCIENCEWORKS CHAIR Ralph Gmell [email protected]

CONFERENCE CO-CHAIR 2004 Ian MacKellar (613) 348-3628 [email protected] CONFERENCE CO-CHAIR 2004 Chuck Cohen See listing in Executive Committee CONFERENCE CO-CHAIR 2005 Anita Ghazariansteja (416) 396-6704 [email protected]

VIRTUAL LIBRARY CHAIR Dave Erb [email protected] COMMUNICATIONS EDITORIAL COMMITTEE Maurice DiGiuseppe (416) 483-0591 [email protected] STAO WEBMASTER Dan Eberwein [email protected]

HONOURARY PRESIDENT Erminia Pedretti [email protected] EXECUTIVE ASSISTANT Paul Weese STAO Membership Office Box 771, Dresden, ON; N0P 1M0 1-800-461-2264; FAX 1-800-754-1654 [email protected] MANAGER, STAO SCIENCE STORE Ian MacKellar (613) 348-3628; FAX (613)348-1006 [email protected]

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MINISTRY OF EDUCATION Denis McGowan (416) 325-2523 [email protected] FRANCO-ONTARIEN Marc G. Lecompte (613) 744-8344 [email protected]

FACULTIES OF EDUCATION Peder Nielsen (519) 268-1807 [email protected]

Institutional Representatives UNIVERSITY REPRESENTATIVE Dr. Greg Finn See listing in Executive Committee

CAAT REPRESENTATIVE Vacant

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RESIDENT’S MESSAGE

My name is John Henry and I am the new President of STAO/APSO. I received my chemistry degree at the University of Hull in England where I taught in a Grammar School for 4 years. In 1969 I moved to Hamilton and taught in a number of secondary schools and became Head of Department and also Special Education Consultant. For nine years I was also a Science Consultant in charge of science from Junior Kindergarten to OAC. This is my 40th year of teaching and during the last six years I have been teaching one semester per year at Westmount Secondary School in Hamilton. During the last six years I have been an active member of the STAO/APSO Safety Committee giving many workshops on ‘Be Safe.’ When the ‘Stay Safe’ project was introduced I became the Project Manager and oversaw its successful completion. There are many challenges for STAO/APSO in the next year. The principal one is the review of the new science curriculum which will start in September 2005. STAO has to be ready to present your views to the Ministry and we will be doing this in a variety of ways, especially at the conference. Teachers will be asked to

enry John H ent id Pres STAO

fill out questionnaires and your comments will help us greatly in our presentation. Alan King’s study on retention of students has had a considerable impact on the Minister. Over the summer we have had a writing team prepare science articles which can be used to help students develop literacy skills. They will be available on the STAO/APSO Website (www.stao.org) in the early fall. We hope your students will benefit from this project. The STAO/APSO Conference will be held in Toronto at the Doubletree

International Plaza Hotel on November 11 – 13, 2004. The theme for this year’s conference is ‘Managing Change for Successful Learning.’ The conference planner is complete and as expected, the Program Committee has done an amazing job. You should have received the conference program along with this issue of Crucible. I urge you to read through it early so you may plan your conference visit. With over 200 speakers, I’m sure you’ll want to take in many of the excellent sessions being offered. Don’t forget to book your hotel room early if you are attending from outside of Toronto. We were able to obtain a generous grant from Merck to produce another edition of the calendar for Elementary School teachers. It will be sent to every elementary school in the early fall. We hope that you will find it very useful and be able to use it with your classes. I am looking forward to a very challenging year and hope to meet your needs as science teachers. Feel free to contact me through the STAO/APSO First Class site: [email protected]. I wish you all a very successful and enjoyable year.

Get ready for STAO/APSO 2004! November 11-13, 2004 Mark your calendar today, and don’t miss out on this excellent professional development experience!!

For full details, visit www.stao.org September 2004

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QUESTIONS • COMMENTS • CONCERNS who to call . . .

Crucible – General Ray Clement (416) 235-5906 (bus.) (416) 235-5744 (fax) [email protected]

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!

Advertising Terry Price (905) 939-8104 (home) [email protected]

Membership/Magazine Mailing 1-800-461-2264 (Now accessible throughout Ontario!) [email protected]

?

Policy Matters Paul Weese (800) 461-2264 [email protected]

!

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MOVING?

Financial Matters Dr. Greg Finn (905) 688-5550, x.3528 [email protected]

Professional Development Malisa Mezenberg (416) 367-8033 (home) [email protected]

Let STAO know...

Name: Membership No.: Old Address:

Deadline schedule for Crucible & Elements Please make note of these dates on your calendar! Issue

Number

Deadline

November 2004 January 2005 March 2005

36.2 36.3 36.4

Sept. 7 ’04 Nov. 5 ’04 Jan. 5 ’05

This deadline applies to all articles, illustrations, and advertisements which must be submitted (preferably on hard copy and accompanied by an electronic version -- Macintosh or .rtf files preferred) to: Shayla Gunter-Goldstein, Assistant Editor, Crucible, Ste. 307, 8 Roanoke Rd., Toronto, Ontario, M3A 1E6 or e-mail articles to: [email protected]

New Address:

New Telephone: Please forward this information to: STAO Membership Office Box 771, Dresden, Ontario. N0P 1M0 1-800-461-2264, fax to 1-800-754-1654 or email: [email protected]

PLEASE INCLUDE THE GRADE LEVEL FOR WHICH THE ARTICLE MAY BE USEFUL.

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CIENCE IN EDUCATION

Improving Scientific Literacy Using Fermi Questions This article is based on a presentation given by the author at the 2003 STAO Conference.

Introduction We all have some notion of what constitutes scientific literacy; it is a basic familiarity with how the world works. Scientific “common sense,” some might call it. This term also connotes a basic facility with concepts in mathematics. It goes without saying that at this point in history and in our culture, a truly literate individual must also be scientifically literate. Major efforts are underway in the developed world at this time to improve scientific literacy. Indeed, the Natural Sciences and Engineering Research Council of Canada (NSERC), one of the most prominent agencies that funds scientific research in this nation, has recently announced a program – Centres for Research in Youth, Science Teaching and Learning (CRYSTAL) – aimed specifically at these concerns. The economic and political consequences of a scientifically literate workforce (or a lack thereof) have been frequently addressed; a scientifically literate person can participate more effectively in society. A science teacher, however, has a more immediate focus: enhancing students’ scientific literacy improves their critical skills, their general reasoning capabilities, and gives students a sense of whether their answers are reasonable. Additionally, scientifically literate individuals are less apt to succumb to growing pseudoscientific temptations in our society — from alternative medicine to psychics. It is important to appreciate the distinction between scientific literacy September 2004

««« By Michael De Robertis Michael De Robertis teaches in the Department of Physics & Astronomy at York University. He may be reached at: [email protected] and technological literacy. The ability to program a VCR or DVD is an example of technological literacy. Understanding how a VCR or DVD works in the simplest scientific terms, however, is of greater importance and is an example of scientific literacy.

Motivation It is both illuminating and entertaining to provide a few examples of scientific illiteracy or innumeracy taken from everyday experiences to motivate a program to improve students’ skills: 1. To compete with the quarter-pound burger of a well-known fast-food chain, another fast-food chain offered its customers a “one-third pound burger.” The new one-third pound burger didn’t sell well because too many people thought that a quarterpound burger was bigger than a onethird pound burger. 2. In a radio interview, a person extolling the virtues of eating peanut butter claimed that the average North American eats 100,000 peanut butter sandwiches in a lifetime. 3. A single bankruptcy lawyer in the USA in 1990-91 billed clients for an average of 1,200 hours of work a month – from a low of 851 hours, to a high of 1,547 hours. 4. “A million, a billion, a trillion dollars; what does it matter, so long as the problem is solved.” 5. In 1990, an advocate for the homeless claimed that homeless people die at the rate of 45 each second in the USA.

While the first three examples may seem almost trivial, there is no doubt that scientific illiteracy can have very serious consequences as the last two clearly show. Perhaps the most disastrous example was China’s socalled “Great Leap Forward” in the mid-1960s which led to the deaths of tens of millions of people. Many of these perished in part because of the scientifically illiterate policies of Mao Zedong.1

Fermi Questions The Fermi Question, sometimes known as the “back of the envelope” question, was named after 1938 Nobel Laureate (in Physics), Enrico Fermi. Fermi used to challenge his students with questions that involved estimation coupled with an understanding of fundamental scientific concepts. Classical Fermi Questions (FQs) include, how many barbers are there in New York City, or how many piano tuners are there in Chicago? Scientists and educators agree that a judicious employment of FQs can enhance students’ scientific literacy at almost any level; from elementary school through to graduate school. It can be quite an empowering experience for students to realize that so much about the natural world can be quantified and is well within their powers of reasoning! Teachers are fortunate that most students find FQs rather entertaining if administered regularly at the appropriate level. continued on page 8... 1 The New Emperors: China in the Era of Mao & Deng by Harrison E. Salisbury, Little Brown & Company, Boston, 1992.

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S CIENCE IN EDUCATION Fermi Questions (...continued from page 7) How to Begin Students have been understandably conditioned to believe that precision is a hallmark of science. It can come as a shock to some students, therefore, that in the case of FQs the answer is of secondary importance to the method of arriving at an answer. (I write “an answer” rather than “the answer,” since a range of answers is acceptable.) This point has to be emphasized repeatedly. By “method,” it is meant charting a rational and logical approach to achieving an answer in the appropriate context. An answer is arrived at by folding in various assumptions and estimating certain quantities where required. Students at all levels should be encouraged to estimate quantities involving familiar situations. For example, at the senior elementary level, students may be asked to estimate things like: • the number of students in their school, • the number of bricks in the school, • the length of the perimeter of the schoolyard, • the number of tennis balls that would fit in the classroom, • the number of blades of grass on the field, • the number of potato chips eaten in the school cafeteria daily, etc. Questions at the elementary level should always be tailored as closely as possible to the local context. More mature FQs require students to be comfortable with fundamental units: length, mass and time, as well as scientific notation. (A desirable byproduct of practicing FQs is that students gain a deeper appreciation of the importance of units and, ultimately, of dimensional analysis to

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solve science problems.) There is no doubt that a little time spent on FQs will pay significant dividends in the long run.

How Many Dentists are there in Ontario? It is useful to illustrate how one approaches systematically a simple FQ since the most frequent question students ask when introduced to FQs is, how do I start? One starts by devising a plan for arriving at an answer, listing all assumptions along the way, and then carrying it out. Basic assumption: there are just enough dentists to accommodate Ontarians if they work a regular (40hour) work week. Plan: • Determine how many patients the average dentist sees each year • Divide the total population of Ontario by this number to arrive at the number of dentists who could be supported In order to find how many people the average dentist sees annually, we make the further assumptions that a typical dentist appointment lasts for about 1 hour and that people visit their dentist twice each year. The solution now follows straightforwardly: Solution: • A dentist treats 40 patients per week (40 hr/1 hr) • Or 1,000 patients per half year (40 patients/week x 25 weeks/half year) • Since there are 10,000,000 children & adults in Ontario, there should be 10,000 dentists (10,000,000/1,000) in Ontario How close is this? According to the Royal College of Dental Surgeons of Ontario, this is well within 50% of the

actual figure. But I wish to emphasize the following: a) There is no exact answer. Providing the logic underlying the plan is correct and the estimation is reasonable, a range of answers is acceptable. So it doesn’t matter if dentists actually work only 35 hours per week on average or take six weeks vacation annually, etc. b) Solving FQs often requires students to expand their horizons beyond what is normally expected of them (e.g., to know the population of Ontario). Moreover, students will soon be able to identify examples of sets with one thousand elements (population of a large school), one million elements (population of a fairly large city), one billion elements (population of the western hemisphere), etc.

More Involved Questions Though it may take some time to think up challenging FQs to give a class, it is well worth the effort. Seeing a few examples is always helpful. Consider then the following questions that may be appropriate for senior elementary school or the first years of high school (with order of magnitude answers or hints in brackets): a) How many hairs are there on your head? [100,000] b) How many times is a basketball dribbled in a game? [3,000] c) How many words are in the school library? (100,000 words/book) d) How many hours have you slept in your life so far? [40,000 for teenager] e) How much garbage is produced annually in your school? (~100 kg/student/yr)

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S CIENCE IN EDUCATION Fermi Questions (...continued from page 8) f)

How far does the entire student population travel daily within the school? (~1 km/student/day) g) How many words are spoken in Canada in one day? [50 billion] h) How much money is spent annually in Canada on pets? [$10 billion] i) How many grains of rice are eaten monthly in China? [30 trillion] j) What is the combined annual salary of all professional athletes who play team sports in North America? [$3 billion] k) What is the total distance a hockey puck travels in a single NHL game? [10 km] l) How many words are printed in all copies of Canadian newspapers in a typical business day? [2 trillion] (Note that some of these questions/answers have important social consequences and so could stimulate discussions beyond the science or math classroom.) FQs may also include a scientific component, though these are normally reserved for more senior high school classes: a) Which exerts a greater pressure; a woman in high heels or an elephant standing still? [woman] b) How many kilograms of water contain about as many molecules as there are drops of water in all the oceans? [~1 kg] c) How many ants does an anteater eat in its lifetime? [40 million] d) How many molecules of air once breathed by Julius Caesar were in your last breath? [~1,000] e) If the iron in Earth’s core were made into a long wire with a cross-sectional diameter of 1 mm, how long would the wire be? [5e25 m] f) What is the minimum amount of September 2004

energy used to make hot coffee/tea consumed by people in Ontario on an average day? [2 trillion J] g) What volume of carbon dioxide is exhaled by Earth’s population daily? [ 100 trillion cubic m] (I am indebted to the American Journal of Physics for some of the questions above.)

Conclusions Fermi Questions can be used to great effect in the math and science classrooms of elementary and high schools (not to mention university classrooms). Their regular usage can lead to students with enhanced criticalthinking/reasoning skills and a greater facility for estimation – scientific “common sense.” Given some thought and placed in the appropriate context, students find Fermi Questions entertaining, making their introduction into the classroom easier on the teacher.

Finally, at the 2003 STAO Conference, I challenged the audience of teachers with the following five FQs. How would you fare? See the shaded box below for the “answers.” 1. How many snowflakes fall on Manitoba annually? 2. How many ice cubes can be made from ice occurring naturally on Earth? 3. If the hairs from the fur of every cat in Ontario are placed end to end, how long would the single strand be? 4. How many notes are played by all the instruments combined during a performance of Beethoven’s Fifth Symphony? 5. The carton containing a 60-Watt light bulb promises a lifetime of 500 hours. How many moles of photons does the light bulb emit in its life?

Answers (As determined by the author who sometimes cheated to ensure his estimates were as close as possible!): 1. 2 x 1019 snowflakes 2. 3 x 1021 ice cubes 3. 1 x 1010 metres (or 30 times the Earth-Moon distance) 4. 1 x 105 notes (there really are apparently 64,137 notes) 7. 1 x 103 moles of photons

Need to reach someone at STAO? STAO has set up a First Class account called “[email protected]”. Messages sent to this account go directly to Paul Weese, Executive Assistant of STAO. We’re looking forward to hearing from you!

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Emerging from the Chrysalis: 10 Tips for First Year Teachers Teachers often expect that after the scramble and stress of their first year on the job, they will attain mastery after the first couple of years. I believe this is not true. Many people plateau and do not improve appreciably even if the desire is there. Conscious planning to improve your practice can lead to long term change. Make raising the bar each year a habit. The following are tips that teachers can use to help improve themselves.

My Top Ten Tips for First Year (and other) Teachers 1. Find a mentor ASAP. I can’t emphasize this enough. Some schools have an official mentor program but if not, there is usually someone in your own department that will unofficially take you under their wing and give you suggestions and help. Most teachers are willing to provide advice on how to achieve best practice. 2. Make a list of things to master: goals for this year and next year. Call it an Annual Education Plan or a list of goals, but students and teachers alike should be making lists of long term and short term, specific, attainable goals. Remember S.M.A.R.T. goals? They are: S=specific, M=measurable, A=attainable, R=realistic and T=tangible. E.g. If your goal is to improve your classroom management skills, how will you go about doing it? When will this goal be reached? How will you know if you have improved? Usually, we have vague goals about “doing better” such as improving classroom

««« By Leila Knetsch Leila Knetsch is a Biology/Chemistry teacher at Winston Churchill Collegiate in the TDSB (Scarborough). management, finishing courses, improving parental contact, making a course more hands-on, being more on top of one’s marking, indeed, being more on top of everything! If you have a four-day turnaround for marking, could you make it a two-day turnaround? Do you want to improve parental contact? How about taking one prep time a week, making a list of 10 students about whom you are concerned, and calling the parents or sending out letters of concern. 3. Set the pace. What you start out doing, you will continue doing. Set a minimum standard for yourself. Give yourself practical short-term goals. An example might be to teach one chapter per week, which includes one laboratory activity, one demonstration and a test or quiz. Be practical! Do not have all your lab days be the same day for every class. Take the ebb and flow of school life into account. On Mondays, students are tired. This leaves Tuesday, Wednesday, Thursday which are (in my opinion) peak theory days. Thursdays and Fridays are optimal lab days and it gives students something to look forward to. Be sensitive to the students. They cannot handle 75 minutes of droning, multiplied by 4 classes. In a week give them one class where they are are teaching themselves (eg. doing worksheets,

learning to do crib notes from the text, solving problems on their own, doing mind maps, etc.) or engaging in cooperative learning (Monday), and perhaps have a demo-lesson on Tuesday. On Wednesday have a regular theory day, Thursday have some theory plus a test or quiz, and on Friday end by complementing the week’s theory with a practical lab component. It could be a full period lab with a full write up due or it could be more of a lesson followed by a process lab such as making soap or bath bombs, ice cream (heat transfer, Gr. 11 Chemistry) or silly putty (Organic Chemistry). If you’re unable to do a “cool” lab or make a product on a Friday (who can come up for something every Friday?), at least try to light something on fire or explode something. It occurred to me that students take science year after year, just hoping and yearning for a good explosion. A good demonstration is the Thermite reaction (see Shakashiri’s demos for more details1) – for grades 9, 10, or 11 chemistry as a single displacement reaction with good connection to societal implications. The Acetylene bomb is another ideal demonstration. If you plan it right, you can fit in a lot of neat stuff to complement the theory and still finish the curriculum. 4. Mix it up – You don’t have to always do a mega-lab each time. Download your workload! Have a

1 B.Z. Shakashiri, Chemical Demonstrations: A Handbook for Teachers of Chemistry, Vol. 1-4, University of Wisconsin Press. Also: Science is Fun Website: www.scifun.chem.wisc.edu

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S CIENCE IN EDUCATION partial write-up sometimes; it will be easier on the students and you in terms of workload. You also don’t always have to have a fullperiod lab. Sometimes it’s great to do a mini-lesson/mini-lab combination. Using a demonstration is a great way to capture student interest and add theory, without all the work of a lab. Besides the entertainment value and the interest created, demonstrations are also a wonderful way to get through to the visual learners out there. 5. Make a month-at-a-glance plan. Print off calendar pages from your computer and determine generally what you are going to teach on which days during the month for a particular subject. Write in pencil and revise as you go along. This is helpful as you don’t have to ask yourself “what am I going to teach tomorrow?” Instead, the question will be “how am I going to teach/get them to learn expectation x/y/z?” Also, you will find that you will finish more of the course if you plan ahead. You will have time to do more labs, activities and hands-on learning that your students (and likely you) long for. Your colleagues might be skipping things because they have run out of time, but you will be able to fit more material in because you planned around the assemblies, shortened days, etc. 6. Scavenge and sort continually. Continue to scavenge for ideas, labs, activities, demonstrations, worksheets, etc. from student teachers, colleagues, the Internet, Crucible, etc. Have course binders with dividers for every subject. When you find something interesting and useful, file it in the binder, under the appropriate unit. This helps you avoid a mad panic when you have to teach a new course. Instead you should have a feeling of excitement since you September 2004

get to use your “mined treasure.” Textbooks from other publishers and old textbooks from previous curricula can also be a valuable source of excellent labs, demonstrations and diagrams. Just because the curriculum has changed does not mean that the scientific basics have! 7. Keep up to date and into the habit of exchanging (not leeching!) with colleagues in your school and elsewhere. With the many people (student teachers, LTOs, etc.) moving in and out of schools, this can be very simple. It’s easy to ask someone for something when you know that you have something that they want in return. Inter-school mail makes this a snap. It’s the old barter system. I will photocopy and send to you five excellent demonstrations for use in each of the Grade 11 Chemistry units in exchange for some interesting items for the Grade 12 Biology Homeostasis unit. Since we know our schedules months in advance, there is loads of time to make these offers. 8. Consider teaching your courses along a theme. I would suggest a Society, Technology and the Environment (STSE) theme. It’s a great way to help raise environmentally conscious young people. Don’t forget about STSE! As a young (or not so young) rookie teacher, there is a youthful optimism and concern for the environment and societal issues. Try to incorporate these into your classes. The theme is already in the

curriculum, although less so than in the last curriculum where it was weaved into every course in addition to being covered in the environmental science and science in society courses which have since been removed from the curriculum. Some teachers have themes running through their courses, and they pull everything together using the theme as the backbone. 9. Take a trip to the library at OISE. A one-day trip to the library at OISE with some cash for photocopying can be very exciting. Make it an annual event! Make a list of the courses you are teaching and some suggested topics and then hit the stacks. There is so much out there. Every year it’s a great idea to load up on good ideas. The difference between a good program and a great program is resources, resources, and more resources. Don’t try to get your courses “in shape” and leave them as is for the next 30 years. The goal should be to refresh and renew, starting on day 1. After the first two years, when you are not as frazzled by day-to-day survival, you will get bored unless you mix it up. Get beyond “survival” mode and onto “mastery” mode. 10. Find a shoulder to unload on. First year is a tough year and it is helpful to have a confidant with whom you can voice your fears, or on whom you can shed some occasional tears. It can certainly have a buffering effect. Good luck!

Science Sillies Teachers have forwarded these answers from test papers, essays, etc. They were submitted to science and health teachers by elementary, junior high, high school, and college students. From time to time, when space is available, Crucible will publish several of these items for your amusement.

“Vacuum: A large, empty space where the pope lives.” “Before giving a blood transfusion, find out if the blood is affirmative or negative.” CRUCIBLE

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The Hardy Weinberg Equilibrium and the Chi-Square Test of Significance: Part II Practice Questions - Using χ2 to test for evolution Part one of this article appeared in Crucible, Volume 35.1, September 2003. Refer to www.stao.org after this issue is published, to see the complete article. How can you tell if a population is evolving or not? Use the χ2 test of significance to help you decide.

««« By Seonaid Davis Seonaid Davis is Co-ordinator, Programs for Highly Able Students at Havergal College in Toronto. She is a regular contributor to Crucible. Just because the observed allelic frequencies calculated from the original genotypic data are used to calculate the expected genotypic frequencies, you might think that it will necessarily show that the population is in Hardy Weinberg equilibrium. Complete the following examples to show that this is not necessarily true. Consider the following data. Is this population in Hardy Weinberg equilibrium? Use your χ2 analysis to check.1

Remember to check your total population size. Numbers of individuals

Genotypes

Allele Frequencies

MM

MN

NN

p

q

Observed

114

76

10

0.76

0.24

Expected proportions

p2

2pq

q2

Expected frequencies

0.58

0.36

0.06

Expected numbers

116

72

12

χ = (o-e) /e

0.03

0.22

0.33

2

2

The results from the χ2 test are nonsignificant. This means that the population is in Hardy Weinberg equilibrium.

Total value for χ2 test = 0.58

Degrees of freedom = 1

Consider the following data2. Is this population evolving? Use your χ2 test to find out. Remember to check your total population size (200). Numbers of individuals Observed

Genotypes

Allele Frequencies

MM

MN

NN

p

q

152

0

48

0.76

0.24

2

2

Expected proportions

p

2pq

q

Expected frequencies

0.58

0.36

0.06

Expected numbers

116

72

12

11.17

72

108

χ2 = (o-e) 2/e

The χ2 test gives a significant result. This means that the difference between the observed and expected results would not be expected to happen by chance alone. The inference is that the population is evolving.

Total value for χ2 test = 191.17 Degrees of freedom = 1

continued on page 13...

1 Adapted from: Crow, J.F. 1986. Basic Concepts in Population, Quantitative, and Evolutionary Genetics. W.H. Freeman and Co., Sand Francisco, CA. Pg 528-529 2 Adapted from: Crow, J.F. 1986. Basic Concepts in Population, Quantitative, and Evolutionary Genetics. W.H. Freeman and Co., Sand Francisco, CA. Pg 528-529 3 Source: R.A. Fisher and F. Yates, Statistical Tables for Biological, Agricultural and Medical Research (6th Edition) Oliver & Boyd, Ltd., Edinburgh

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AREERS IN SCIENCE

Neonatal Nurse: Nancy Yeh Nancy Yeh is a full time Registered Nurse (neonatal nursing) at Women’s College Hospital, where she has worked for the past five years. Ms. Yeh also works part time at Toronto East General. Mrs. Leila Knetsch interviewed her for the first of a series of career profiles that she uses with her students.

Mrs. Knetsch: Would you please describe your job? Ms. Yeh: Some of my duties include basic things like taking the vital signs of the babies (temperature, heart rate, respiration and blood pressure). Also, I perform a head to toe assessment and look for certain things like bruising, body proportion and skin colour – looking for jaundice, etc. I listen for bowel movements and weigh

««« By Leila Knetsch Leila Knetsch is a Biology/Chemistry teacher at Winston Churchill Collegiate in the TDSB (Scarborough). the babies’ diapers to make sure that their bowels are working well. In addition, I check the babies’ breathing and if it is too fast or too slow, I put them on different types of ventilators. Because it is the Intensive Care Unit (ICU), I am constantly monitoring the babies. I take care of babies that are born prematurely, between 23 and 40 weeks. In many cases, these babies have medical problems and need to be monitored. For example, if a mother had a fever before she gave birth, then the baby may need to have antibiotics. In another example, if a mother

has had a Caesarian section birth, the baby can’t get rid of the lung fluid and will have to stay in the ICU due to respiratory distress. Babies also sometimes swallow the meconium (waste) due to stress and have to be on a ventilator for a short time. Infants stay at the hospital from one day to four or five months, depending on their medical needs and how prematurely they were born. Nurses see the parents as well as the babies on a daily basis. Some nurses try to work with certain babies if they have a special connection with the family. continued on page 14...

Practice questions (...continued from page 12) χ2 table of values3 Degrees of Freedom

Probability 95%

90%

80%

70%

50%

30%

20%

10%

5%

1%

0.1%

1

0.004

0.02

0.06

0.15

0.46

1.07

1.64

2.71

3.84

6.64

10.83

2

0.10

0.21

0.45

0.71

1.39

2.41

3.22

4.60

5.99

9.21

13.82

3

0.35

0.58

1.01

1.42

2.37

3.66

4.64

6.25

7.82

11.34

16.27

4

0.71

1.06

1.65

2.20

3.36

4.88

5.99

7.78

9.49

13.28

18.47

5

1.14

1.61

2.34

3.00

4.35

6.06

7.29

9.24

11.07

15.09

20.52

6

1.63

2.20

3.07

3.83

5.35

7.23

8.56

10.64

12.59

16.81

22.46

7

2.17

2.83

3.82

4.67

6.35

8.38

9.80

12.02

14.07

18.48

24.32

8

2.73

3.49

3.49

5.53

7.34

9.52

11.03

13.36

15.51

20.09

26.12

9

3.32

4.17

4.17

6.39

8.34

10.66

12.24

14.68

16.92

21.67

27.88

10

3.94

4.86

4.86

7.27

9.34

11.78

13.44

15.99

18.31

23.21

29.59

Non significant

September 2004

Significant

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C AREERS IN SCIENCE Neonatal Nurse (...continued from page 13) LK: What is your academic background? NY: I have a Bachelor of Science, Nursing from the University of Toronto. It is a 4-year degree. LK: What subjects should high school students concentrate on to enter into the nursing field? NY: Students should have a B+ average and be strong in Mathematics, Science and English. Currently, to be a nurse, students need to take two years of Arts and Science and then two years of a Bachelor of Science in Nursing. Some nursing schools in Ontario are: MacMaster University, University of Toronto, Ryerson University, Queen’s University, York University (new program) and University of Western Ontario. Another option is to do a collegeuniversity collaborative program.

LK: Why did you go into nursing? NY: I have always enjoyed caring for people and thought that I had the qualities that would allow me to contribute to the profession. I think this is something I learned while growing up. My grandmother took care of me and I wanted to repay her. My grandfather was ill and I took care of him. I like the aspect of relationship building. Some patients you see only once, while some patients you see for months and get to know their families as well. LK: What are some of the skills needed for nursing? NY: You must have good communication skills, be a good listener, and be a person that is very respectful of people with different backgrounds. Sometimes people make choices that you might not agree with but you have to respect their choices.

EVENT CALENDAR September

October

10, 17 Star Party @ Science North, Sudbury, 8 p.m. Gaze at the planets, the moon and the stars through powerful telescopes with the help of Science North’s astronomer and volunteers from the Sudbury Astronomy Club. Access a recorded message for updates: 705-522-3701, ext. 243. Admission is FREE for everyone! More info: http://sciencenorth.ca/plan/ calendarofevents/

4-8

16-23

National Chemistry Week. Visit: www.cheminst.ca/ncw/ index.html for more info.

23

National Mole Day. Visit: www.moleday.org/ for more information.

Ongoing Dynamic Earth at Science North. Go inside the planet to explore the mighty forces of nature that impact people and cultures around the world. Visit: http://dynamicearth.ca or http://sciencenorth.ca for more information.

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4th World Conference of Science Journalists, “Reporting the future: Journalism meets emerging science.” Montreal. Visit: http://www.wcsj2004.com for more information.

November 11-13

STAO 2004. Managing Change for Successful Learning. International Doubletree Hotel, Toronto. More details: www.stao.org

There are cases with babies that are as young as 23 weeks old where some people want you to do everything for them even when the outcome is very uncertain due to the fact that they have not finished developing. You also need to be a good team player, have excellent organizational skills, good time management skills, and you need to show a lot of initiative in learning new things and taking on tasks. LK: What is one skill that you need to have as a nurse that you did not expect? NY: You have to be really organized. There is a lot of tracking of patients. There are so many patients and if you cannot organize your time to care for them, that is a problem. Time management is a must. LK: What is the range of pay? NY: The pay starts at $21-33/hr. You get paid more for holidays, plus you can get time and a half or double time pay if you work overtime. LK: What is the worst part of your job? NY: The worst thing is the shiftwork and the long hours. However, there is a plus side when you do two 12 hour days and two 12 hour nights and then get four days off. LK: What do you like best about your job? NY: I love watching the babies become healthier and grow, and then see them go home. It’s really something. It’s nice to know that you had something to do with them being alive. Volume 36 • 1

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CIENCE AND SPACE

Canadian Astronomer gets Rare View of the Universe So, you think that only professional scientists get to do neat things? Think again. On June 28 and 29, I (a teacher and amateur astronomer) had the opportunity to use the 40-foot radio telescope at the National Radio Astronomy Observatory (NRAO) facility in Green Bank, West Virginia. About 300 years ago, an explosion occurred in our galaxy which signalled the end of a massive star’s life. The star was 11,000 light years (104,068,800,000,000,000 km) away. The expanding shell of material which remains from that explosion is known as Cassiopeia-A and is moving outwards at more than 16,000,000 kilometres per hour. The remnant of that supernova explosion can still be detected by astronomers today. While Cassiopeia-A is only one of many galactic supernova remnants or SNRs, it is one of the objects which I attempted to detect while in West Virginia. In the early morning hours of June 28, I swung a huge 12-metre diameter antenna into position.

««« By Philip Gebhardt Philip Gebhardt teaches evening science courses at the Palmerston Community School in Whitby, Ontario.

Although the antenna looks like an oversized satellite dish, this antenna did not pick up satellite TV programs. It was peering 567,648,000,000,000, 000,000 km into space at the constellation Virgo. I waited for 25 minutes as the antenna and Earth rotated under the stars. Finally, a weak signal began to appear. It continued to increase over the next 5 minutes, then peaked, and then in the following 5 minutes it decreased and disappeared. I had detected a radio source known as Virgo-A. Over the next several days, I detected several other radio sources, some with unusual sounding names like 3C10 and W28. It was truly exciting. The NRAO is one of the world’s premier research facilities for radio astronomy. The NRAO operates powerful, advanced radio telescopes which scientists from around the world use to probe fundamental questions in astronomy and physics. The NRAO operates the Robert C. Byrd Green Bank Telescope (GBT), the world’s largest (100 by 110 metres) fully steerable radio telescope, as well as several other telescopes. I used the NRAO’s 40-foot (12-metre) telescope for my study. These telescopes are large versions of the satellite dishes found on many homes.

Philip adjusts the motor control to position the NRAO’s 40-foot radio telescope to receive a radio signal from 3C10. The control room is located underground to prevent signals from the equipment interfering with the telescopes. September 2004

While many people still think of astronomy as a visual science, astronomers today also study objects that emit radio waves, infrared radiation, x-rays and gamma rays. Objects such as

Philip Gebhardt poses with the 40-foot (12-metre) diameter radio telescope which he used to detect 3C218 Cassiopeia-A act as huge radio transmitters which send out signals that can be received here on Earth. These objects emit radio signals on frequencies similar to FM radio stations, TV stations, cell phones and satellites. Because of the enormous distances, the signals are extremely weak when they reach Earth. Large antennas and sensitive receivers are needed to detect the signals. Last year, I studied x-ray astronomy techniques at the National Space Science and Technology Center (NSSTC) in Huntsville, Alabama in a program sponsored by NASA. The NSSTC is a collaborative research and education initiative of government, academia and industry that serves as a laboratory for cutting-edge basic and advanced scientific research. The centre also fosters the education of the next generation of engineers and scientists. continued on page 16...

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S CIENCE AND SPACE Rare view of Universe (...continued from page 15) These are just two examples of the opportunities in science which are available to everyone today, but would have been open only to professional scientists 25 years ago. For me, using a radio telescope at NRAO is like a hockey fan getting to play with the Maple Leafs or a baseball fan playing with the Blue Jays. In August, I headed back down south to do some work with an astronomer from the University of North Carolina who runs a week-long workshop called Educational Research in Radio Astronomy. Graham Mogford, an amateur radio astronomer in the U.K. who has also participated in a similar radio astronomy experience sums it up this way, “It’s a great feeling actually using a radio telescope and seeing your data come in. I know when I was driving home from after first using it, I suddenly thought, My God, I’ve actually seen the structure of the Milky Way for myself, not just read about it! It’s amazing when you stop and think about it.” In 2001, Philip and his elementary school students conducted the Great Loop Antenna Experiment in which

Stellar Know-How Want more information about radio astronomy? It’s as close as the Internet. You can uncover the “hows” and “whys” of radio astronomy at http://www.nrao.edu/whatisra/index.shtml or take a short course in radio astronomy at http://www2.jpl.nasa.gov/radioastronomy/. For images of radio telescopes and the objects which radio astronomers study, start with http://www.nrao.edu. This site will show NRAO telescopes, but there are radio telescopes all over the world. If it’s a hands-on approach you’re looking for, you can learn how to detect meteors in “All Rock Radio” (Crucible, September 2001, p. 13) or Sky & Telescope (December 1997, p. 108). Or, you and your students can actually detect radio emissions from Jupiter and solar bursts from the Sun. To hear signals from Jupiter, go to http://www.astro.ufl.edu/radioobs.html#Sounds . Detecting Jovian radio signals is relatively easy. Hundreds of schools around the world have been involved with NASA’s Radio Jove project. See http://radiojove.gsfc.nasa.gov/

they built a square (3-metre sides) box antenna on the lawn of the Whitby Public Library. They demonstrated how it received AM broadcast stations from as far away as New Orleans, Moncton and Winnipeg. (See Crucible, Volume 33.4 March 2002.) He has also worked with high school students at Trafalgar Castle School introducing them to the radio detection of meteors.

In 2002, he received the Science Teachers’ Association of Ontario’s Irwin Talesnick Excellence in Teaching Award. This year, he received an Ontario Arts Council grant to teach pinhole photography. Phil Gebhardt may be reached at 905642-9718 or by email at: [email protected]

Crater Creator So you’re out shopping for groceries, and you see in your rear view mirror that a 200 meter-wide iron asteroid has impacted the ground 10 kilometers away. Bummer! It’s sure to form an impact crater, create a firestorm, and otherwise ruin your day (as well as melt the ice cream you just bought). So, should you high-tail it in the opposite direction, or just go about

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««« By Phil Plait Phil Plait, a.k.a. The Bad Astronomer, publishes a Website and newsletter on astronomy. Visit the Bad Astronomy site at: www.badastronomy.com your business? Now these decisions are easier to make! The good folks at the Lunar and Planetary Laboratories have created a web page where you can enter the parameters of the impact (asteroid size, composition, etc.) and it will return a cheery and optimistic

look at how badly you’ll be killed by the ensuing explosion. Fun for the family! Here’s the page: http://www.lpl.arizona.edu/ impacteffects

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NASA Brain Bites Provide Answers for Curious Minds The next time a student asks you, “How do you go to the bathroom in space?” or “How long would a round trip to Mars take?” you can answer with a NASA Brain BiteTM. NASA Brain Bites are a series of 60second video shorts to be used as a learning tool in helping educators and parents answer questions students have about space or aeronautics, or to introduce classroom activities on topics such as gravity, acceleration, motion, friction, Newton’s Laws and more. Not only will these video shorts help feed hungry minds but they will help students gain a better understanding of how space science and aeronautics work. Do your students know what launch windows are and why NASA uses them when sending a crew into space? If not, then let Super Bowl Champion Quarterback, Kurt Warner help (spaceflight.nasa.gov/brainbite/ launch). Warner explains that a launch window is similar to a play in football. For a space mission to meet its target, such as the moon or a distant planet, it must take off in a certain time period. Warner explains the same is true in football. When he throws the football, he doesn’t aim directly for his teammate, instead, he aims for where the ball will intersect his teammate’s path. Whether launching a football or launching a spacecraft, timing is crucial. If you take off at the wrong time you might miss your target completely. Students are also interested in finding out how astronauts train here on earth. NASA can’t send astronauts into space to work on the International Space Station if they have never had training in a simulated zero-gravity environment, so there are a few ways September 2004

««« By Jenna C. Mills Jenna C. Mills is an Education Officer with the Johnson Space Centre in Houston, Texas. space travelers can train. One way is with a specially modified plane called the KC-135, also termed the “Vomit Comet,” (spaceflight.nasa.gov/ brainbite/vomitcomet), and another is a giant swimming pool called NASA’s Neutral Buoyancy Lab, (spaceflight. nasa.gov/brainbite/underwater). Both give astronauts the necessary training they need to work adequately in space. NASA Brain Bites can easily go along with a science lesson, and they answer questions in a way that makes it easy for middle and high school students to understand. Teachers and parents can also get their students’ directly involved with Rocket Science at Home (RSAH), which works in conjunction with NASA Brain Bites. NASA hopes this will stem further interest, get students more intrigued with science and hopefully take what they have learned to explore more concepts of science on their own. By visiting the NASA Brain Bites Website, students can learn how to build a hovercraft with the help of a

teacher or parent (spaceflight.nasa. gov/brainbite/rocketscience). This activity can be integrated into the classroom or as a Saturday afternoon project. It’s a great way to get students directly involved with science principles and build something really cool at the same time. You can view the NASA Brain Bite videos by visiting brainbites.nasa.gov, where you will also find links to supporting educational material, including gradeappropriate activities that are mapped to national standards. Brain Bites can be downloaded from the web at no cost, in presentation-level quality, for educational purposes at any time. In the near future, you will be able to obtain a videotape copy of NASA Brain Bites for your classroom through NASA CORE at 1-866-776CORE or core.nasa.gov, or through your area NASA Educator Resource Center. For any additional information, you may also contact Jenna C Mills at 281-483-9261 or email the team at [email protected].

Have you liked the stories and activities you’ve read so far? If so, and if you’d like to be able to get other relevant and useful activities, worksheets and interesting articles for classroom discussion on an ongoing basis, you should join STAO today! You’ll get five issues per year of Crucible and Elements, plus so much more! Visit www.stao.org for membership information.

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CIENCE IN THE CLASSROOM

Growing with your Students This information is recommended for use with the Ontario Curriculum, Grades 3, 4, 6, 7 & 8: Life Systems Grades 3 & 5: Earth and Space

This activity fits into the curriculum in the following strands: Life Systems for Grade 3 (Growth & Changes in Plants), Grade 4 (Habitats & Communities), Grade 6 (Diversity of Living Things), Grade 7 (Interactions Within Ecosystems and Grade 8 (Cells, Tissues, Organs & Systems). It also works into Earth & Space for Grade 3 (Soils in the Environment) and Grade 5 (Weather). It also fits into Grade 9 Biology (the curriculum specifically mentions bulbs in the academic stream, but reproduction is covered in both academic and applied streams). It can also fit into Grade 11 Biology (genetic continuity). Starting a school garden has many advantages, and this is the time of year to capitalize on those advantages by planting spring-flowering bulbs. Clearly, a garden enhances the science curriculum. Students not only learn about plant parts, their needs and the life cycle of plants, they learn about soil, aspects of weather and how plants relate to the animal kingdom and ecosystems through a hands-on, applications-based activity. Scientific horticultural names provide a great introduction to classification systems. All living organisms fit into a hierarchy which includes kingdoms, divisions, classes, orders, families, genera and species. Your students will need to apply research and planning skills. Record keeping skills can be developed or reinforced. Beyond that, they learn how to work together. When students

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«««

By Philip Gebhardt and Sandra Cooper

Philip Gebhardt teaches evening science courses at the Palmerston Community School in Whitby, Ontario. Sandra Cooper is an educational assistant at Eagle Ridge Public School in Ajax. within your class, different classes or even different grades work together and take time to get to know each other, the results are a positive school environment. Ultimately, the students will have a beautiful garden of which they can be proud. That brings with it a sense of accomplishment and satisfaction. It also builds a sense of caring and of taking responsibility for their surroundings. Unlike many science activities, bulb planting is not a one-hour science lesson. It gives the students an opportunity to engage in an on-going, long-term project. One of the benefits of planting a bulb garden is that it includes a life lesson: postponed gratification. Students will not see the results of the work they initially do for at least five or six months. The best part though is that bulb planting is easy and almost failsafe.

What’s In a Bulb? The term bulb is often loosely applied to a range of subterranean food storage organs. This covers tunicate bulbs (tulip), scaly bulbs (lily), corms (crocus), tubers (anemone) and rhizomes (iris). We’ll focus on the true bulbs (tunicate and scaly), corms and tubers since this is likely what you will plant with your students at this time of year. True bulbs produce foliage and roots from a flattened area at the base of the bulb known as the basal plate. The bulb itself is a compressed stem and the fleshy scales are modified leaves. The scales have growth buds at their bases and enclosed flower bud initials that will produce the coming year’s

flowers. Tunicate bulbs, such as tulips, daffodils and onions, have a papery outer skin (the tunica) which is the dried remains of the previous season’s scales. Their scales are arranged in concentric rings which radiate from the bulbs’ centre. Scaly bulbs – lilies for example – do not have the papery outer layer. Instead, they are composed of small, overlapping scales. Lilies have many scales whereas fritillaria have only two or three. A corm (crocus is one example) is the swollen base of a stem. A corm is usually rather flattened and solid. Like a tunicate bulb, it has a papery covering which can be peeled away. Removing the covering reveals the growth eyes on the upper surface. A tuber (anemone is available in the fall) is the swollen part of an underground stem. The tuber is usually rounded with various protrusions and depressions which contain the buds (think of a potato).

Is It Science or Art Class? Planting bulbs is an opportunity to put your students’ knowledge of light and colour to work. Discuss whether to have a monochromatic bed or a polychromatic bed. Should you use only primary colours or should you include secondary and maybe tertiary colours? Which colours would be harmonious; which ones would be complementary? One way to investigate which colours work together is to look at multicoloured flowers (pansy for example) and variegated foliage (perhaps coleus). Why do the petals of a red tulip appear red in sunlight? What colour would the Volume 36 • 1

S CIENCE IN THE CLASSROOM petals appear if the light source were green? Your students can design and conduct experiments to predict what will happen and then test their prediction with red tulip petals in the spring. Depending on what colours your students’ garden incorporates, you can help them to discover that warm colours (red, orange, yellow) appear to come forward while cool colours (blue, violet, green) recede.

The Bulbs Need a Home When looking at locations, try to find an area that has 4 to 6 hours of sunlight per day. Bulbs will tolerate some shade, but lots of sunlight will encourage larger flowers and will enable the bulbs to produce and store the food they will need for successive years. Also, blooming will be delayed if the bulbs are in shade. Good soil drainage is important because the bulbs will rot in wet soil. If the soil in your area does not drain well, you can add sand to improve drainage. If the area drains too quickly and doesn’t retain water, you can add material from the school’s compost bin or buy soil amendments (such as peat moss, humus, well-rotted manure, grass clippings, composted leaves, hay, straw or almost any organic material) from a nursery. The size of the proposed garden will need to be taken into consideration. It is wise not to start out too large, as filling it can not only be daunting, but expensive. A garden near the front of the school works well as it becomes a welcoming sight not only for those involved with the school, but for the community at large. Why not let everyone admire the hard work the students do? In addition, locations in the rear of the school may be subject to unavoidable damage from recess play and soccer balls.

Bulbs and Euclid Meet You may not have much choice where to put your bulb garden. But if you do, there are many options open to you to September 2004

make the garden interesting and to help motivate your students. As a class, discuss what shapes you could use. Depending on size and location, you might consider simple square, rectangular, triangular or circular shapes. Beyond that, think about crescents. You might even incorporate various geometric shapes within a single bed. Of course, you could throw caution to the wind and settle on an irregular or freeform shape. Your students can draw their garden designs to scale on graph paper. After you have a design, decide whether to plant the bulbs in rows, to scatter the bulbs or to group the bulbs in clumps.

Individualism Can Be Better – Sometimes Once you’ve made the basic decisions related to the type (or types) of bulbs to plant, the colours to use, where to locate your garden and the shape of your garden, then it’s time to buy the bulbs. You can buy bulbs individually or in bags. Either way, choosing healthy bulbs is key. Bags are less expensive, but you can choose a wider range of colours and varieties if you buy individual bulbs. By opting to buy individual bulbs, you can handpick large bulbs. Generally, large bulbs mean large flowers. You can also inspect individual bulbs. You can feel the bulbs: hard bulbs are good; soft bulbs are not desirable. You want to avoid bulbs which have been damaged or show signs of disease. Different bulbs flower at different times, so don’t expect a spectacular display of crocus, tulips and daffodils simultaneously. This is a good reason for planting in clumps (at least seven bulbs per clump). That way you can intersperse different bulbs. When they do flower, you will have clumps placed throughout the garden so no matter what bulbs are blooming it will look as if there are flowers everywhere — there will be no obvious bare spots. Even tulips will bloom at different times. There are early season

A bulb cutaway bloomers, midseason varieties and late season types. If you want to extend your display of blooms, vary the planting depth of the bulbs. Bulbs planted deeper will bloom later than shallow planted bulbs. Varying the planting depth of the bulbs is an opportunity to discuss variables that affect the outcome of an experiment. There are many effective ways to offset the cost of a bulb garden. Think about having a bulb drive. Ask parents to donate a bulb, or have the school buy the bulbs and have students contribute to help offset the cost. You may want to talk to your local nursery and ask them to donate some bulbs for your venture. Many nurseries are more than happy to donate to schools because it is good advertising for them and it encourages future gardeners.

The When and How Deciding when to plant the bulbs is straightforward. It needs to be done before the first frost. If you’re not sure when that is in your area, ask at a local nursery. The real criterion is that the soil temperature should be below 15°C. Parents are a great source for gardening tools. Ask if any parents are willing to lend, or better yet, donate some old, but useable tools. You will need 2 or 3 shovels, a garden rake, and some hand held trowels. A wheelbarrow will make mixing soil easier, but this can be done by placing a garbage bag on the ground and simply placing the soil on top of it. A wheelbarrow also will help with the cleanup! If you do not have access to an outdoor tap, you will need 2 or 3 watering cans. continued on page 20...

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S CIENCE IN THE CLASSROOM Growing with your students (...continued from page 19) Here are 5 easy steps to a perfect bed:

• Finish off by mounding the soil slightly above ground level. (It will sink as it settles.)

1. Prepare the bed • Dig the bed to a depth of 25 to 30 cm and then thrust your digging fork into the bottom of the hole to aerate the bed a bit more.

4. Water • Water to a depth of 25 to 30 cm to encourage root growth.

• Next, return a couple of centimetres of the soil you removed to the bottom of the hole so that the bulbs will rest on loose, free-draining soil with no air pockets. Mix bulb food (usually a superphosphate) or bone meal into this soil. These will help to feed the bulbs and promote root growth. (If you’re up to it, you can replace these with well rotted manure.)

5. Mulch • Do not mulch until after the first major frost. If you mulch too early, the wet mulch will promote both disease and rot. • Mulching helps control weeds and conserves soil moisture. Use leaf mold, compost, shredded bark, or other attractive organic materials. The mulch can be 2.5 to 5 cm deep.

• Smooth the bottom surface to make it level. 2. Firm the bulbs in place • Place the bulbs in the bed in the design of your choice • Keep the pointed growing tip (the nose) of the bulb on top and press the rounded bottom (the basal plate) into the loose earth. • Set the bulbs at a depth equal to three times their diameter. (For tulips, that’s about 15 cm.) • Space large bulbs about 15 to 20 cm apart; space small bulbs about 5 to 10 cm apart. • Gently press the bulbs into the soil, so they are in good contact with the soil and so they will not move when soil is returned to the bed. • At this time, you might want to put 2 or 3 bulbs on their side and another few upside down as a test to determine what happens. 3. Fill in the bed • Shovel the soil in gently at first, so the bulbs don’t get jostled out of position.

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Mulching beds

How Did We Do That? Record keeping is an integral part of any scientific activity. Consider using photography to supplement your records. Be sure to photograph the garden area before you start work. That way, you’ll have ‘before’ and ‘after’ pictures. Photograph the site and the students as work progresses and maybe even take a shot or two in midwinter when the bed is buried in snow.

Linking to Other Subjects Once you’re this far, the possibility of linking bulb planting to other science and technology topics and to other subject areas seems natural. Although bulb planting is an easy activity, it lends itself well to extension studies. What soil type do you have in your school yard. Is it clay? Is it sandy? Clay soils don’t drain well; sandy soils drain too quickly. How can you modify

the soil to make it more suitable for plants? Then there’s weather. Since bulbs need to be planted before the first frost date in your area, there’s research to be done to find out about that. Will you need to water the bulbs so they don’t dry out or will there be sufficient rain? Rain means clouds and a study of cloud types. Are there beneficial insects in your garden or will you need to deal with pests? Did your students find worms when they dug up the soil? If not, should you import some worms? What do worms do for a garden anyway? Although the bulbs have enough stored food to carry them through their first season, they will eventually need nutrients to restock the bulb for succeeding years. What fertilizers are available? Will you use chemical fertilizers or organic fertilizers? Read the labels on fertilizer containers with your students. What’s nitrogen? (And why do plants need it?) Hang on, nitrogen is a gas. Shouldn’t it escape when you open the container? What else is in fertilizer? Once you have investigated the chemical symbols listed on the package, what other symbols can your students uncover? Once you’ve exhausted the science and technology possibilities, you can move on to other subject areas. Math works well here. Of course, your students will need to use linear measurement to plant their bulbs at an appropriate depth. What’s the perimeter of the garden? What’s its area? If your students dig down 30 cm to aerate the soil and break up the clumps, what volume of soil will they have worked? Based on the area of your bed and the separation between bulbs, your students will be able to estimate how many bulbs they will need. This might be a mathematical calculation or on a drawing of the bed. That will lead to cost calculation. Once they know how many bulbs they continued on page 21...

Volume 36 • 1