LEARNING SET 1: A CLOSER LOOK AT OUR RIVER What is the Water Like in Our River?
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LEARNING SET 1: A CLOSER LOOK AT OUR RIVER CONTENTS Science Understanding for Teachers
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Lesson 1: What is Water Quality
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Teaching Strategy: The Driving Question Board
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Lesson 2: What Can We Find At Our River?
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Lesson 3: How Can We Ask Good Questions?
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SCIENCE UNDERSTANDING FOR TEACHERS Introducing Students to the Quality of Water in Their River Learning Set One introduces the driving question “What is the Water like in Our River?” and creates the context for inquiry. Sharing a common experience, students use a river walk, , or a virtual tour to make observations and develop questions about their river and its water quality. In this section, students observe the fluvial and floodplain ecosystems associated with their river. Student observations are directed through teacher input and student worksheets.
River Walk Information Marking Your Territory River observations will be more meaningful to the students if the boundaries of the study area are clearly defined. This will keep students focused and facilitate discussion. Chose a site that is as large as feasibly possible while ensuring legal, safe, and easy access. Site boundaries should be well defined, fixed (e.g. bridges, road crossings, buildings, etc.) and easy to distinguish from site maps. Maps aid in the initial survey and serve as a reference for future investigations. Giving the students a base map will help orient them to the area. During the river walk or video students add their own observations to the map. This will help facilitate student ownership of the project as they collect and depict their own data. Their maps should detail watershed drainage patterns, land use, vegetation, pollution sources, and other features important to water quality. It may be necessary for students to make more than one map to minimize clutter and confusion. Maps should be kept in a project file and updated as needed.
Physiography While on the river walk, pay particular attention to the physiography of the watershed. The physiography is the physical shape of the land. It determines how the water flows across the watershed, the land area that drains or seeps water into your river. Take note of topographic features such as hills, valleys, and flat areas that may affect the way that water is drained or “shed”. For instance, more water moves over land faster on steeply sloping terrain than on gently sloping terrain with the same soils. Have students add the topographic features of the study site to their maps.
Fluvial Ecosystem When students are looking at the plant and animal communities within the river, they are observing a fluvial ecosystem. A fluvial ecosystem is a complex community of organisms functioning as an ecological unit within the environment of moving water. Plant and animal life within the ecosystem are immediately impacted by the quality of water in the river.
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Floodplain Ecosystem Flooding is a natural event wherein the river swells with high discharges of water, exceeding its banks and submersing the floodplain. The floodplain ecosystem is shaped by the force and nutrients provided by floodwaters. Rivers flood naturally in the spring of the year, when there is a high amount of precipitation and melting snow. Likewise, rivers may flood during heavy fall rains. Humans have attempted to completely stop flooding in many cases and inadvertently increase it in others. Decreasing the frequency and severity of natural flooding harms both fluvial and floodplain ecosystems by hindering nutrient exchange and removing the force that shapes the floodplain ecosystem. On the other hand, increasing flooding creates a much greater force of water than fluvial and floodplain ecosystems are equipped to handle. Extreme floods (e.g. created by combined sewage overflow) create rapidly moving waters that pick up a great deal of sediment. The result is very murky, sediment-filled waters, and severely eroded stream banks. How has your community historically dealt with the river’s natural potential to flood? Are portions of the river moving through concrete channels? Is it dammed, diverted, culverted, or straightened? Have students look for the answers to these questions in the area surrounding the river. All of these structures have been used historically to moderate the impact of flooding on riverfront property and road crossings. Map any such structures, and note the possible effects. Look for evidence of flooding while on the river walk. Pay particular attention to debris in the bushes and trees. This debris can be an indication of how high the water was during the last flood. Also, there is often a fairly obvious watermark on tree trunks. Once you have determined how deep the water was, you can imagine the dimensions of the flooded area. The water must have filled the land adjacent to the river to that depth.
Vegetation Floodplain plants are adapted to frequent flooding. These plants can tolerate very moist conditions and periodic inundation. As a result, the main plant components in this ecosystem are trees and vines. Shrubs cannot tolerate periodic flooding. A large shrub component in the floodplain can indicate a reduced flood frequency. Floodplain plants protect the health of the stream and the bank. These plants stabilize stream bank soils, reduce the risk of erosion, and absorb many of the pollutants that would otherwise enter the stream. Floodplain vegetation also provides shade that cools the water. As a result, an intact tree canopy is very important to stream health. Note whether the canopy is mainly intact or open. Plant material that falls into the river becomes food for many stream organisms. In fact, fall leaf litter is a primary food source for many stream insects. In addition, insects attracted to the bank vegetation become part of the food supply when they fall into the river or lay their eggs there.
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Larger pieces of fallen debris offer habitat features for aquatic animals. Woody debris in the stream offers shade and resting/hiding habitat for fish. Fallen logs can also alter the flow of water creating habitat diversity (e.g. pool and riffle habitat). Too much debris can be harmful to the health of the stream. Debris dams that occur naturally provide temporary habitat variation. However, human-incited debris dams (e.g. debris caught on bridge supports) can have long term effects on stream habitat and flow. Unlike naturally occurring dams, human-incited dams are difficult to break and move downstream during a flood. Instead, they continue to collect debris and litter, strangling the flow of the river, and limiting the movement of aquatic animals. Pay particular attention to natural and man-made structures that severely restrict the flow of water in your river.
Bank Stability Bank stability is an indication of its resistance to erosion and collapse. Stable banks are not easily worn away by the action of water, wind, or ice (i.e. erosion). Bank vegetation is a major component of bank stability. Well-vegetated banks can be 20,000 times more resistant to erosion than comparable banks without vegetation. Herbaceous vegetation is the most effective vegetation for bank stability because of its many, spreading, deep, fibrous roots. Woody plants are helpful as well, but they are not as efficient in stabilizing the very top layer of soil. The roots of woody plants are often deeper and coarser. Gently sloping stream banks are more stable than steeply sloping banks. Steeply sloping banks are those with a slope greater than 30 degrees. As mentioned earlier, more water moves over steep terrain faster than it does over gently sloping terrain. This means that a steep bank is more likely to erode away with water moving quickly over its surface. Steeply sloping banks are usually the result of severe erosion, and are often a sign of poor floodwater management and very erosive stream flows. Some undercutting of banks is beneficial, like some woody debris in the stream, because it provides shade and resting/hiding habitat for fish. Bank angles that are less than 90 degrees usually improve habitat. However, severely undercut banks are susceptible to collapse. Stream bank modifications are often used to reduce soil erosion. The presence of stream bank alterations indicates that erosion is a problem at the site. Rocks, wood, metal and concrete reinforcements are commonly used to reinforce stream banks. However, plants are also used for bank stability in ecological restoration projects. Plantings can be very effective, while providing secondary benefits as well. Estimate the condition of the left and right banks in your study site. Note that the right bank is on your right side when facing downstream. Wildlife It may be possible to visually observe wildlife while on the river walk. Look for animals in the air, on land, and in the water. If no animals are seen, students can look for evidence of wildlife, such as feces, tracks, and nests. If animals are seen, take note of what the animal is doing. It can be an indication of habitat quality. For instance, if you see a fish gasping for air at the surface of the water, dissolved oxygen in the water is probably very low. On the other hand, if you see an animal drinking
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water from the river, it can indicate that the water is safe for animal use. Sounds can be an indication of wildlife and habitat quality as well. Listen for birds warbling, frogs croaking and insects chirping. If you hear a lot of industrial noise and traffic, that can be a sign of noise pollution. Too much noise disturbs native animals, and can scare them away from a habitat that might be good otherwise. You may also observe domesticated animals, such as cats and dogs. Their presence is a detriment to habitat quality. They are nonnative animals, and often kill native animals (e.g. cats that hunt and kill birds). Note anything that might limit animal movement in the stream. Animal movement is very important for migrating animals. Obstructions, such as “hanging” culverts, man-made dams, debris dams, and dewatered portions of the river limit aquatic animal movement.
Land Use Now that we know that surface runoff is a major source of water in the river, let’s begin thinking about how various land uses affect the river’s water quality. What pollutants or wastes would surface runoff from various land uses bring into the stream? How is the land next to the river being used? Classify adjacent land uses as agricultural, residential, commercial, industrial, natural areas, and/or recreation. Instruct students to map the various land uses near the river. Paying special attention to the magnitude and relative proximity of each land use, note how each may be influencing the river. Look for land uses that may impact water quality in your river. Negative examples include construction sites (barren soil), manicured lawns, crop and animal farming, mining, parking lots, roads, industrial and sewage treatment plants, open dumps, and landfills. An overabundance of animal and human users can also be a threat to water quality. Natural land uses preserve water quality by maintaining the natural balance of the water cycle and absorbing pollutants. Natural areas and vegetation are the best land uses to preserve and protect water quality. Pollution is anything added to the land or water that lowers its ability to be used by plants, animals and humans. Pollutants can refer to any toxic substance in the water or essential substances (naturally occurring) that at increased or reduced levels lower the water quality. Illegal dumping is a source of pollution. Illegally dumped items are pollutants on their own, and can be a source of slowly leaching chemical and nutrient pollutants. Note the presence of litter, tires, appliances, car bodies, shopping carts, and garbage. Similarly, note any evidence that excess nutrients have been dumped into your river such as grass clippings, cut branches and other types of yard waste. Legal dumping sites (e.g. landfills, open dumps, sewage treatment ponds and junk-yards) can also be a source of pollution for the same reasons as illegal dumping. However, they have far-reaching consequences and may not be as easy to visually observe during the river walk. Another source of pollution can be pipes entering or near the stream. Note any pipes with visible openings discharging into the stream, even if it is not evident what they are dumping or where it is coming from. Also, note other pipes near or entering the stream even if you cannot find an opening or see matter being discharged.
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Water Appearance The appearance of the river can provide useful information about the water’s source and content. The apparent color of water results from dissolved substances and suspended matter. Pure water absorbs different wavelengths (colors) of light at different rates. The wavelengths of light that are best transmitted through water are blue and green, so a white surface under “colorless” water looks blue (e.g. Caribbean waters above white sand). However, the addition of various pigments and ions can alter the transmission of light and apparent color. Therefore, the appearance of the water can be an indication of the water’s content. Some of the appearances can indicate harmful pollutants others do not. A complete list of colors, sources and effects can be found in Table 1. There are also indicators of water quality, meaning that one measure of stream health can point to the condition of the entire system. Previously mentioned indicators include a shrub component in the floodplain ecosystem, animal actions, the presence of macroinvertebrates and more.
The Water Cycle The water cycle explains the continuous cycling of water from the atmosphere to land to oceans and back again. Solar energy powers the water cycle. The sun’s energy drives evapo-transpiration, which transfers water from land, plants and open water bodies into the atmosphere. This water is later returned to the land and open water through precipitation events such as snow and rainstorms. The precipitation that hits the land can become surface run-off (flowing over land), evaporate back into the atmosphere or follow a variety of alternative pathways as it percolates down into the earth. The precipitation that is absorbed into the soil can be taken up into plant roots, move along the subsurface eventually reaching the river, or move deep into the earth to replenish the aquifer or groundwater. This process is known as ground water recharge. Water that is stored in the aquifer will be slowly released into various water bodies. Although there are a variety of avenues that precipitation can take on its way to the ocean, it is important to understand that evapo-transpiration, surface runoff and percolation the the three major pathways. through the soil are the three major pathways
Water Quality Physical and chemical changes within floodplain and fluvial ecosystems alter the quality of the river’s water. Initially, students may have trouble understanding the concept of water “quality”. Using the words “health” and “quality” interchangeably will help reinforce the concept. Quality is often used to refer to “how good” something is or “how well the ‘thing’ does its job or serves a purpose”. Quality can also be related to how much money something is worth. For instance, a Cadillac is considered to be a very high quality car. Giving the students examples from their everyday life can facilitate comprehension. Water quality may be difficult to understand because it is relatively defined. It is based on the judgement and intended use of the evaluator. What is good water quality to one person may be poor water quality to another. Also, a person’s determination of water quality is relative to the streams s/ he has seen before. Determining water quality is dependent on mental reference sites that the evaluator can use for comparison.
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Due to various experience levels and values, it may be difficult for the class to reach an initial consensus on the quality of water in their river. Use this to your advantage. It can be a great opportunity to explore the values used in determining water quality, and the need to develop water quality standards.
Determining Water Quality One must conduct a large number of tests to determine water quality for there are a large number of variables influencing water quality. No one test can undeniably determine water quality. However, the information provided by multiple tests can depict overall water quality. Tests allow us to determine the presence and abundance of different chemical or physical variables in the water.
Summary In this Learning Set students explore the concept of water quality and what that might look like in their local river. Through observations of land use, types of vegetation, wildlife, and bank stability, and water color students will begin to realize that various factors and pollution sources influence the water quality of the river. In turn, these conditions influence which organisms are able to live within the river. Using their observations data they collect, students will begin to make educated inferences about their river’s water quality and what other evidence they will need to obtain to make a more conclusive answer to what is the water like in their river.
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LESSON 1: WHAT IS WATER QUALITY? OVERVIEW AND OBJECTIVES Learning Objectives Through visually exploring water quality samples and group discussion students will develop their own list of characteristics of water quality.
Assessment Criteria Characteristics of water quality will be based on student observations and be testable.
Purpose Students are guided through a series of experiences that involve making observations and predictions of several water samples. This activity helps students think about ways of judging water quality. Students conclude this lesson by learning about the investigation(driving question) they will conduct on their river in the following weeks.
PREPARATION Set-up Water Quality Jars Collect the materials and set-up the five “Water Quality” Jars. Fill jars 1 - 4 3/4 full of water. Jar 5 will be filled with river water. Jar ONE Add enough coffee grounds and cocoa powder until the water has a good "dirty" look. Label the jar "ONE." Jar TWO Add a pinch of potassium permanganate. The water should appear a clear purple color. Alternately, add two drops of food coloring - enough to slightly modify the color of the water. If doing this, avoid blue if at all possible (to avoid student misconceptions about water being blue). Label the jar "TWO." Jar THREE Add a trace of hydrochloric acid. The HCl solution should be clear and colorless. Label the jar "THREE." Jar FOUR Add a few tablespoon full of kosher table salt to the water. The salt will dissolve in the water resulting in a clear colorless solution. Label the jar "FOUR."
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Jar FIVE Fill a jar or beaker 3/4 full of water from your local river. Label the jar "FIVE."
Special Considerations • If you plan to go to the river collect signed permission slips.
Materials • • • • •
Signed permission slips if going to the river Graphic materials for the driving question board 5 large jars with lids or soda bottles with lids Clip, coffee, cocoa, salt, HCl, isopropyl alcohol, potassium per manganate or food coloring for a purple color, local riverwater Student Worksheet/Exploring Water Quality
Time One fifty-minute period.
INSTRUCTIONAL SEQUENCE Introducing the Lesson Introduce the students to the investigation they will conducting over the next several weeks (driving question) "What is the water like in our river?" This question will organize the project over the next few weeks. Inform the class that as they learn about their river they will be creating models and conducting tests on their river to determine the river’s water quality.. Talk about the role of main investigation question (driving question): Scientists use questions to focus their investigations and research. Questions help researchers know what information to look for and how to organize and think about the information they find.
Conducting the Lesson Exploring the "Water Quality" Jars In small groups have students examine jars. You may choose to have the students record their observations on the Student Worksheet/Exploring Water Quality or in their journals. Ask the students to come to consensus as a group to determine which of the water samples they would be willing to use for such things as fishing, swimming, boating or drinking. After students have observed all the jars have them share their consensus and rationale for their decisions regarding water use. Prompt students to provide evidence for their decisions. (You may also choose to record the classes data in a chart on the board. This would allow students to graph the data in their journals, additionally the data could be used as evidence for student statements.)
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Using this shared experience, facilitate a discussion to lead to a consensus definition of water quality.
Establishing Links Have students brainstorm answers to these questions: What is meant by quality? What is water quality? How can we determine water quality? Why is water quality important? How did we determine water quality for the bottles? How else could we measure water quality? Prompt students to takes notes and record the key ideas and the classes definition of water quality in their journals to revisit as the investigation continues.
Concluding the Lesson Conclude with the students to the next experience in the project, “the river walk or video”. Students begin the investigation by exploring their local river. This exploration will be accomplished through a video, virtual tour or a river walk. If feasible it will also be supported by the creation of a river tank in the classroom. The observations they make during these activities will be used as evidence to make a conclusion to their investigation (driving question). Connect the river walk to the “water quality” jar activity •
• • •
-Re-visit the “how can we determine water quality questions?” -Introduce the Student Worksheet/River Observation or specify what types of notes are to be taken in their journals. How does the Student Worksheet/River Observation, or journal notes organize our observations? -What are we investigating? -What kinds of details are we looking for? -What information can we get from a river walk that we couldn’t get from the jar activity? -Tell students that one outcome of the walk or video will be to help us make our first response to our driving question.
ASSESSMENT • Student Worksheet/Exploring Water Quality
HOMEWORK Provide students with articles from their local newspapers that refer to water quality in their local river or other rivers in the area. Choose articles that address living organisms in the water or human uses of the water and describe how members of their community talk about their river or are taking action to prevent or reduce water quality problems.
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TEACHING STRATEGY THE DRIVING QUESTION BOARD The Driving Question Board (DQB) is a visual display for the project in your classroom. The DQB refers to a bulletin board or a poster space on a wall in your room where class artifacts from the project are collected and displayed. The DQB serves as a means to help students recall the important events and conceptual ideas developed in class as they progress through the project. Featured in the center of the DQB should be the driving question, What is the Water Like in Our River? By featuring this question prominently in the classroom, students are reminded of the purpose and goals of participating in this science unit. As the project progresses, post major class artifacts on the DQB. These include the initial brainstorming lists, observations from activities, lab work, and class definitions. Suggestions for artifacts to post on the DQB are made throughout this curriculum guide. In particular, the DQB provides a place to display ‘works in progress’, such as accounts of students’ developing understandings or a repository for potential investigation questions they may pursue later in the project. Use the DQB to stimulate discussion about ideas or concepts that students may be confused or unsure about. Throughout the project, the DQB can provide a unique and comprehensive summary of the work you and your students have accomplished that can be shared with parents and others who visit your classroom.
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LESSON 2: WHAT CAN WE FIND AT OUR RIVER?
OVERVIEW AND OBJECTIVES Learning Objective Using observations and evidence obtained from their river experience, students will apply characteristics of water quality and formulate a hypothesis regarding the water quality in their river.
Assessment Criteria Students’ hypotheses’ of their river’s water quality will be supported by evidence obtained during observations of their experience and are testable.
Purpose Students will have an opportunity to observe a local river. Observations are made of the topography, living organisms, natural and human-made constructions, and human influenced physical characteristics of the river. There are three alternatives for this session: • • •
Take a river walk. Watch a river video Go through the virtual tour.
Taking the river walk is preferable, allowing students to experience first hand the natural world that exists in their urban community. However, if taking a walk is not feasible, watching a river video or virtual tour is a good alternative. It is also highly recommended that you build a classroom river tank. A river tank allows students to see the many processes involved in a river system, present additional observation opportunities and is useful for getting students excited about rivers. It can also be used later during the macroinvertebrate identification, and can be referred to throughout the unit.
PREPARATION Set-up River Walk, video, or virtual tour options For the virtual tour, have the computers ready and become familiar with the observations the students could possibly make.
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For the video option, sign out a VCR and monitor. If feasible, create a video yourself of a river walk. have someone assist in taping you as you go to your river and point out important indicators of water quality. If taking the river walk, be sure permission slips are in, transportation is arranged for and extra adults have been contacted to assist in supervision. Video If you are unable to take students to your local river, you may want to see if it is possible to take the river to your students using a self-made video recording. This is probably the best alternative to an actual visit in that the video would be made by you or your students, and would feature a local site that students may be familiar with, and ideally, would become familiar with later in the unit when visiting the site for the water quality testing activities. To do this, we recommend that you visit the site at least once prior to the recording of the session, so that you can identify features of the water, river, and local land that may be important for students to understand with respect to the driving question. Possible strategies might include recording the site yourself and narrating as you go with questions you would pose to students about the site, or my having someone record you with a videocamera as you point our and narrate aspects of what the camera is seeing for your students. This approach can also be useful in that you and/or students would be able to revisit the site by watching the video again, and ongoing preparation is not needed (you can use the video in future years as is). Otherwise, if you do take students on the river walk, and have access to a videocamera, we would recommend that you record aspects of your walk and river site visit, so that you and/or students can review the visit again as needed to understand local phenomena.
River tank You might want to set up the tank a few weeks prior to the beginning of the project if possible. In the model river, the 10 gallon aquarium serves as a pool and the trough serves as the riffle. (See Teacher Resources for set up.) You should only introduce the tank at this point, but refer to it later in the unit. Virtual Tour The virtual tour is an opportunity for students to see a river site and all of the various features of a site if they are unable to visit an actual site at this point in the unit. This should not be viewed as a first step, but rather, an alternate learning experience should it not be possible to visit the river site first hand, or to create a video of a local site within your watershed. The virtual tour provides opportunities for students to revisit the river often and make connections between classroom activities and the real world. The virtual tour sites are shown on the Investigate the State website (http:// www.investigatethestate.org).
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Special Considerations • • • •
Signed permission notes if taking a river walk River video that you buy or make yourself If using the virtual tour reserve computer time or make arrangements for computers to be ready in your classrooms. Extra time might be needed if creating the river tank
Materials • • • • •
• • •
River video or virtual tour (if not doing the walk) river video/walk Observation Sheet Butcher paper Markers River tank -10 gal aquaria -1 meter plastic trough or rain-gutter with cap for one end -1 submersible circulating aquaria pump with filter and screen -flexible pvc or rubber tubing, 2-3 cm in diameter -Sunny window or Florescent plant growth lights Student Worksheet/Watershed Virtual Tour Student Worksheet/River Observations student Reader/Closer Look At Our River
Time Two fifty-minute periods.
INSTRUCTIONAL SEQUENCE Riverwalk or Video of River Walk Review the key points from the previous activity. Review the class’ ideas about the following two questions: • •
What is water quality? How can you determine water quality?
Explain to class that today we are starting our investigation by making observations from a river video, virtual tour or walk. Distribute river observation worksheets and maps according to your choice of river experience. Describe what observations to make, for instance, at varying elevations observable at the river. The class watches a video or walks along your local river. If walking, you may wish to take a videocamera with you to record the walk for later use or review by students. Prior to and during the walk or video, prompt students to make observations about various aspects of the river that they might not otherwise consider, such as the following. As students make observations have them record their observations on their maps, Student Worksheet/River Observations or journals. • • • • • • • •
Flow of the river (direction and speed) Size of the river (depth and breadth) Shape of the river (Straight, bends, etc.) Vegetation near the river (type, amount, relative health, etc.) Banks of the river (size, shape, what is on the banks, etc.) Any man-made features near the river Local sites and land use near the river Animals or organisms living in or near the river
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As the video or walk unfolds stop so the students can make notes of their observations. Students share observations Small groups share their initial hypothesis, to the driving question, and critique the responses based on the description of evidence included in the responses, such as natural and man-made constructions and physical characteristics of the river.
Debrief of the River Walk or Video Observation Review the driving question. Explain to class that today we are continuing our investigation by reviewing our river observations and developing a hypothesis to our main question Pass out observation sheets and river map from previous day, or the journals in which the students took notes. Within each small group have students share and compare their maps and observation sheets. Have each group share their comparisons and observations with the whole class, and provide feedback on characteristics of quality observations . Explain that observations are just one type of evidence and might not show the entire picture (some water jars were misleading) Have students use their “Student Worksheet/What is the Quality of Water?” or journal notes to compare the water from the river with the other 4 “water quality jars” from Lesson 1. Students complete the information for jar 5 - the river water. Ask the groups to formulate an initial conclusions to the driving question in the form of a hypothesis. If your students are not familiar with the idea of a hypothesis take time to go over or review what makes a good hypothesis and why they are important and useful in science.) Remind them it is an investigation, and in order to confirm our hypothesis we will have to gather evidence. Some prompts to help facilitate this discussion may include: • • • •
What evidence of nature (living and non-living) did you observe? What answers on your worksheets did you use as evidence? How does the river water compare to the other 4 jars? What evidence is there that people have affected the river?
HOMEWORK Describe family extension assignment. (Optional) Students walk along their local river with their parents or guardians. Students make general observations of what they see, hear, and smell. Have all involved record their observations.
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Safety Note: Be Careful! While taking the students to their own river can be an invaluable learning experience, it can also be very dangerous. Be certain to take proper precautionary measures for yourself and the students. Avoid contact with River water. Although the water might be cleaner than it has been in the past, many rivers are still unsafe for human contact due to heavy loadings of untreated sewage and stormwater pollutants. Hence, it is important to wear protective clothing, such as impermeable waders when entering the stream and latex gloves when taking samples. Make certain that each student uses a pair of disposable, latex gloves when taking river water samples. Note that some students are allergic to latex. These students can use rubber gloves.
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LESSON 3: HOW CAN WE ASK GOOD QUESTIONS?
OVERVIEW AND OBJECTIVES Learning Objective Through sharing and evaluating of other classmates questions, student swill construct valid questions based on the criterial of a good question, and will develop a set of questions that will help them explore and answer the driving question.
Assessment Criteria Students’ questions will have no straightforward answer, will require multiple resources to answer, will relate to the driving question, will develop understanding of science concepts, and cannot be answered without data.
Purpose Students develop questions to further their investigation of the driving question. Products are constructed from their observations and placed on a Driving Question Board (DQB).
PREPARATION Materials • • •
Index cards or post-it notes Butcher paper, whiteboards, or decorative paper to cover the DQB Markers
Time One fifty-minute period.
INSTRUCTIONAL SEQUENCE Discussion of Good Questions Prompt students to think if they now know enough about the river to answer the Driving Question. (They should not.) Critique some of the responses from the previous days to introduce the need for asking more questions in order to answer the big Driving Question. This may be accomplished by: • • • •
Describing how student artifacts lead them to think about other questions. Asking the class why questions are an important part of science Recording student responses on the board. Critiquing and editing questions to refine them to address the desired outcome.
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Based on your review of the questions students generated, discuss the following criteria for good qustions that scientists would ask themselves before exploring the answers to these questions: • • • • •
Question are interesting to you to pursue The questions have no straightforward “yes” or “no” answer, one-sentence answer, or even paragraph answer. The questions require multiple resources to answer The questions cannot be answered without some evidence (such as data or other information related to the question) The questions relate to the driving question that is being studied.
Summarize the class’ reasons for asking questions, and make sure to address the concept that questions help scientists focus their investigations, and help researchers know what information to look for and how to organize and think about the information they find.
Connecting to the Driving Question Connect the ideas generated in the previous discussion about “good questions” with the Driving Question: “What is the water like in our river?” Explain to students that this question is very large, so we need to think about smaller questions that will help us organize what we learn about the Driving Question. Have students generate sub-questions that can help address the bigger Driving Question in some way. For instance, “Where did the water in our river come from?” is a good question that also requires some thought, and would be necessary to answer first before we can address the driving question. You can have students generate sub-question in two ways: either generate questions on their own by writing down questions and sharing them aloud with the class in discussion afterward, or have students brainstorm these sub-questions in small groups for a short period, and then have them organize the questions in some manner to decide which ones need to be answered first, and which can come later. You might give the previously listed question as an example. In order to address the question “Where did the water in our river come from?”, students would need to know how water gets to the river. Whereas, “what is in the water?” might be addressed later when tests of the water are done. If students are brainstorming answers, have them write each question on an index card or post-it note (one question per card), so that these can be organized on a whiteboard or butcher paper later. After students have brainstormed a list of initial questions, review the criterial for good questions, listed above, so as to edit individual questions or thin the list of total questions within any group. Then, students should organize these by content, trying to generate a list of what would first be studied before other questions. You should then select cards created by the students with their questions to post on a Driving Question Board or some other visual organizer, so that students can see the order of the questions you will be studying in this unit. You may need to adjust these to follow the sequence of the unit, to remove inappropriate questions for the unit (or those that might distract from answering the driving question), and add questions that link to specific lessons of this unit that students did not generate on their own.
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