Chapter Iii Research Methodology

CHAPTER III RESEARCH METHODOLOGY

This chapter presents and discuses the subject of the study, the research design, the instrument used in manipulating the data, and the statistical tools in interpreting the data.

Subjects of the Study The respondents of the study were the 80 selected third year high school students of sections Newton, Einstein and Masunurin of Iligan City East High School – Sta. Felomina, Sta. Felomina, Iligan City. The respondents were grouped into two. This was obtained through pairing based on sex and grades in the first grading period in: Mathematics, MAPEH, and Science. Group A was subjected to PowerPoint presentation and Group B was exposed to “Do-ItYourself” instrument. There were 40 students per group with 15 males and 25 females.

Research Design The quasi-experimental method of research was utilized which employed single pretest and post test design. Furthermore, the researchers used simple random method in selecting the respondents.

21 Methods of Gathering Data In gathering the information and data needed, each group was given a pretest and posttest formulated based on the RBEC competencies to determine the change of students’ performance before and after exposure to the two approaches. The study was conducted during the “Palakasan” a sports and literary event of Iligan City East National High School, Sta. Felomina. During this time, the respondents from the different sections were pulled out and grouped into two. On the first day of the research, the pretest was conducted on the three sections (Newton, Einstein and Masunurin). On the second day, the respondents were exposed separately to the approaches on the topic volume and temperature relationship, atmospheric pressure was introduced on the third day, boiling point and pressure relationship on the fourth day, electrolytes and non-electrolytes on the fifth day, and Tyndall effect on the sixth day. The posttest was then given on the seventh day. Then, the data were tallied, tabulated and analyzed.

Research Instruments A constructed questionnaire was used as an instrument for gathering the data. There were 11 questions on volume and temperature relationship,11 on atmospheric pressure, 16 on boiling point and pressure relationship, 16 on electrolytes and non-electrolytes, and 11 on Tyndall effect summing up to 65 questions based on the Table of Specification. To ensure the validity of the

22 instrument, the constructed questionnaire was thoroughly face validated by the adviser. Lesson plans for the selected topics in Chemistry was made for both “DoIt-Yourself” instrument and PowerPoint approach. Lesson plans for both approaches were thoroughly face validated by the adviser. Adapted activities for the selected topics in Chemistry taken from an unpublished thesis were utilized for the “Do-It-Yourself” instrument approach. Gadgets for the selected topics in Chemistry were also adapted from National Science and Technology Instrumentation Center which were further improved by the author of the unpublished thesis. The students were grouped into eight with five members per group. Developed PowerPoint presentations on the same topics were designed exposing the students on the same time allocation as that of the laboratory approach. The PowerPoint presentation was then thoroughly validated by the experts in Chemistry and some practice teachers prior to its application in the class. A rubric was utilized by the experts and by the practice teachers in validating the PowerPoint presentation. The PowerPoint presentation per topic employed graphics designs which were projected on the white screen to maximize visibility of the presentation by all of the respondents in the group.

23 Statistical Technique Used The data obtained were analyzed using the following:

1. Percentage (%). This is used to determine the performance level of the students from pretest to posttest. The formula used to compute percentage is, Percentage (%) = f/N *100 Where, f = frequency of respondents N = total number of respondents 100 = constant used to convert decimal number to percent.

2. Mean. This is used to determine which of the two approaches caused better performance among the respondents on the selected topics in Chemistry. The formula used to compute the weighted mean is n

Σ xi Weighted mean (x) =

i=1

N Where, nn

X = weighted mean

Σxi Σxi = sum of the responses i=1 i=1

N = total number of respondents

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3. Mann-Whitney U test. Nonparametric test was employed to test the significant difference between the use of “Do-It-Yourself” instrument and PowerPoint presentation approach. Results of this test were obtained using the statistical software program Statistical Package for the Social Sciences (SPSS). The Mann-Whitney U test is the most popular of the two-independentsamples tests. It tests that two sampled populations are equivalent in location. The observations from both groups are combined and ranked, with the average rank assigned in the case of ties. If the populations are identical in location, the ranks should be randomly mixed between the two samples. The test calculates the number of times that a score from group 1 precedes a score from group 2 and the number of times that a score from group 2 precedes a score from group 1. The Mann-Whitney U statistic is the smaller of these two numbers.