Verne A. Troxel
Science Education Miami University Oxford, Ohio 45056
Comparison of Achievement of Students in High School Courses
Since the advent of the CHEMS and CBA chemistry materials, many teachers have been in a state of confusion as to whether they should use these new materials. This report is an attempt to objectively analyze the effectiveness of the CBA (1, %), CHEMS (5, 4),and "Modern Chemistry" (5) course materials utilizing and comparing student achievement of various common objectives of the three courses of study. The effort of this research was funded by the Bureau of Research, Office of Education, and the results may help
EDITOR'SNOTE: For those of our readers unfamiliar with the terminology and procedures of educational researchers we have a brief explanation of F-tests m d confidence limits. Three recommended references on the statistical treatment of data are also included for further information on the derivation and theory of these techniques. The F ratio is used to determine whether there is a statistically significant difference between two or more meens. If the F ratio is significant, i t is an indication that two or more means differ significantly among themselves. The formula for determining the F ratio is detailed in reference (I). There is a range on either side of the mean value within which the true value can be expected to fall. The limits of this range within a certain probability are called the confidence limits. The true d u e of the mean could be expected to fall within the confidence limits with a given probability. Confidence limits can be calculated by a number of methods. These include calculations of the confidence limits of the mean, the range, and of the standard deviation. Assuming normal distribution of the measurements, the limits can also be estimated within which individual measurements would fall. The confidence limits for the mean value of a set of measurements can he found in references such as, "Statistical Treatment of Experimental Drtts" (3) where tables are available to supply values to determine confidence level desired based upon the number of measurements.
teachers to make their choice between the two new programs and the more conventional approach to chemistry.' A number of individuals have researched the effectiveness of these courses both subjectively and objectively (6-11). To summarize the results of these efforts, the common objectives of the three chemistry courses under investigation were found to indicate that the student utilizing any one set of these materials should: (1)develop a better understanding of science, (2) develop a background in chemistry, (3) develop an appreciation of science in terms of a positive attitude toward science, (4) develop an ability for critical thinlcing. For this study four instruments were used on a pretest and post-test basis to determine if there was any difference in the attainment of the objectives of the three chemistry courses. The objective instruments were as follows2 (1) ACS Cooperative Examination in General Chemistry, Form 1963 (ACS) (15) A. Recall of Information (1) B. Applicat.ions of Principles (2) C. Quantitative Application of Principles (3) D. Total Test Score (4) (21 , , Test on Tinderstandine Science. Form W. (TOUS) . . 1181 . . A. The Scientific Enterprise ( 5 ) B. The Scientist (6) C. Methods and Aims of Science (7) D. Totsl Test Score (8) (3) Wetson-Glaser Critical Thinking Appraisal, Form Ym, (WGCTA). (17). A. inference (j) B. Recaenition of hsumotions (10) . . C. ~ e d u i t i o n(11) D. Interpretation (12) E . Evalustian of Arguments (13)
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References (1) NEIDIO, H. A,. YIN~LIN-, R. T . , AND G R I B ~ O LR. D ,E., Chamistry, 40, 28,1967. , Foundation8 of Eduoationsl Re(2) SAX. G ~ ~ . e e n r"Empirical
search," Prentice-Hell. Ino.. Englewood Cliffs.New Jersey, 1 9 6 8 , ~ .422.
(3) Y o u ~ a .Hnax D., " S t a t i s t i d Treatment of Eiperimenthl Data." McGrhw-Hill Book Company. Inc., New York, 1962.
1 The full report may be received on loan from the writer or t,he Office of Education. Request the report for contract number OEC3-7-078025.3133, project number 78125. 2 Numbers in parentheses after subtest titles are the numbers used for these tit,les on tables in t,his report. The validit,y and reliability of these instruments are generally available and are included in the full report.
Volume 47, Number
I , hnuory 1970
/
79
Table 1.
MC CHEMS CBA
Summary of Analysis of Covariance Results for the Total Group of "Modern Chemistry," CHEMS, and CBA Students
x x
x
-
-
x
x
x
x
x xx
x xx
x I
x xx
x x
x x
x x
Y
x x
x
13
14
XX
Y
Numbers 1-15 refer to the subtests and total tests as defined previously in this report. x Indicates significance aver group left blank but not over group marked with a - or another r. xx Indicates significance over the other two groups.
Table 2.
MC CHEMS CBA
Summary of Analysis of Covariance Results for G r a d e 10 Students Enrolled in "Modern Chemistry," CHEMS, and CBA
1
2
3
4
5
x xx
x
x xx
x
x
x
7
8
9
x
x x
x
6
Y
10
11
12
x x
x
15
x x
x
x Indicates significance over group left blank hut not over group marked with - or another x. xx Indicates significance over the other two groups. Table 3. 1
MC CHEMS
Summary of Analysis of Covariance Results for Grade 1 1 Students Enrolled in "Modern Chemistrv." ,. CHEMS. and CBA
2
x
3
4
5
x
x
x x
6
7
8
9
x
x
x
10
11
12
13
14
x x
X Indicates significanceover group left blank but not over group marked with a - or mother x.
CR A
x
x
15
x xx Indicates significanceover the other two groups. Toble 4. 1 MC -. .. ..
CBA
2
Summary of Analysis of Covariance Results for Grade 12 Students Enrolled in "Modern Chemistry." CHEMS, and CBA 3
4
5
6
7
8
xx
xx
x
x
x
xx
x
F. Total Test Score (14) (4) Prouse Subject Preference Survey, (Prouse) (18) A. Total Test Score (15)
Extreme care has been taken to assure randomization during the selection procedures in order to assure meaningful statistical r e ~ u l t s . ~Including all subtest and total test scores, each student received and answered a battery of fifteen examinations. A total of 1333 students and twenty-three teachers took part in the study in Iowa and Illinois. Since it was possible for size of school, background of teachers, and number of students to be quite variable, the following criteria were met in the study: (1) Teachers had to have a minimum of 35 semester hours of college chemistry. (2) Schools had to have a minimum of 500 students in grades 10-12. (3) Teachers had to have a background in the type of chemistry they were teaching through institutes, i.e., CBA teachers-CBA institutes, "i\Iodern Chemistry" teachers-General Chemistry institutes, etc., inservice training, or through having taught the course for more than one year. Each teacher was considered to be implementing the philosophy of the particular course materials which he was using. All the teachers agreed to administer the pretests the first two weeks of the fall semester and administer the post-tests the first two weeks of April. The students were compared on the basis of: (1)
/
10
11
12
13
14
x
x
x
Y
15
~~
x
x Indicates simifieance over group left blank hut not over group marked with a xx Indicates si&ificauce over