rollment in schools of all sizes in a given science by the total number of sections reported in that science from the sample. The overall average class size as shown in the "total" category does not appear to have been excessive in any single science course. As might be expected, the average class size in 9th-grade general science, biology, advanced general science, and "other sciences," is somewhat larger than in physics and chemistry. The size of school does appear to have been a determinant of the average class size. Every science shows a progressive increase in average class size from the smallest through the largest schools.

Table 28 shows, by grades in school, a comparison for 1954, 1956, Table 28.-Average Size of Certain Public High School Science Classes, by Grades in School: Fall 1954, 1956, and 1958

As

and 1958 of the average class size in certain science courses. mentioned previously, the categories of school types were changed slightly in the 1958 study from those in the previous studies. The Johnson study made in 1947-48 indicated the average class size at that time as 26 in general science and biology, 23 in chemistry, and 19 in physics. The 1956 offerings and enrollment study showed an average class size of 28.9 in general science for all high schools. Considering the three specialized sciences, biology, chemistry, and physics, there has been relatively little change in average class size over the past decade. The average class size for general science has changed but slightly over the past 2 years. A slow and gradual increase in average class size for the three specialized sciences seems to have occurred in the

576457-61-7

4-year period from 1954 to 1958. However, since the changes are small, they may not be statistically significant.

The grades in the school appear to have been a factor in determining average class size when the 4- and 6-year high schools are compared with those having only grades 10, 11, and 12. For each of the years under consideration in the table, and for each science course, the average class size was larger in the 3-year senior high schools than in the 4- and 6-year high schools.

Table 29 distributes the data on average class size for the years 1954, 1956, and 1958 according to geographic region. A comparison of the average class size for all regions shown in table 29 with the average class size 10 years ago, in each of the three specialized sciences, shows that there has been an increase of 2.1 pupils in biology, 0.27 in chemistry, and 1.6 in physics. This seems to indicate that class sizes in science for all geographic regions have tended to change but slightly. For most geographic regions and for most sciences there has been relatively little shift in average class size since 1954. However, there are a few exceptions: for example, chemistry in the Pacific

region, physics in the West North Central region, and "all other sciences" in four regions. It should be pointed out that even these apparent shifts might be due to sampling errors.

Table 29.—Average Size of Certain Public High School Science Courses, by Geographic Region: Fall 1954, 1956, and 1958

The science data in this study can be summarized in a number of short statements under appropriate headings. These statements follow below.

Offerings

1. The percentage increases from 1956 to 1958 in the number of schools in the two samples that enrolled pupils in the 9th, 10th, 11th, and 12th grades and offered general science, biology, chemistry, and physics in those respective grades are shown in the following tabulation:

2. The most commonly offered sciences in the schools of the sample and the percentages of those schools offering them are the following:

3. Advanced courses in biology, chemistry, and physics, as well as project research seminars were offered by a small but significant number of schools in every part of the country.

4. The number of schools offering chemistry and physics has increased percentagewise to a greater degree over the past few years than has the number offering general science and biology.

5. The number of senior high schools offering biology, chemistry, and physics has changed very little percentagewise over the past few years; but the number of 4-year and 6-year high schools offering these subjects has increased steadily, percentagewise.

6. From one geographic region to another, a wide variation is revealed in the percent of schools offering various science courses.

Enrollments

1. General science. The percent of the total high school population enrolled in 9th-grade general science grew steadily between 1928 and 1956, but in the last 2 years this growth appears to have been arrested, showing a slight decline from 21.8 percent in 1956 to 21.2 percent in 1958. Despite this percentage decrease the actual number of pupils enrolled in general science shows an increase from 1,518,000 in 1956 to approximately 1,581,000 in 1958.

2. Biology. The percent of the total high school population enrolled in biology has continued the steady growth begun in 1910. During the last biennium it increased from 20.5 to 21.3 and the actual enrollment grew from 1,430,000 to approximately 1,677,000.

3. Chemistry. In terms of the total high school population the percent of students enrolled in chemistry is at an alltime high for this century. The actual number of pupils enrolled is likewise at an alltime high. The current study shows an increase from 7.5 percent to 8.9 percent and from 520,000 pupils to 657,000 between 1956 and 1958.

4. Physics. The downward trend in the percent of the total high school population enrolled in physics, beginning around the turn of the century, may have been arrested, since the current study shows

a small increase over the past 2 years from 4.4 percent to approximately 5 percent. It is estimated that the enrollment increased from 309,600 to 379,000.

5. Advanced sciences.-The percent of pupils enrolled in schools not offering advanced science courses ranges from 79 percent for advanced general science to 94.8 percent for advanced physics.

6. Schools not offering certain sciences.-Ten percent of all 9th graders were in schools enrolling 9th graders but offering no general science; 3.6 percent of all 10th graders were in schools enrolling 10th graders but offering no biology; 8.3 percent of all 11th graders were in schools enrolling 11th graders but offering no chemistry; and 13 percent of all 12th graders were in schools enrolling 12th graders but offering no physics.

7. Schools offering neither chemistry nor physics.-Only 9.9 percent of the schools enrolling 12th graders offered neither chemistry nor physics and these schools enrolled only 3.3 percent of all 12th graders.

Ratio of Boys to Girls

Over the past decade the number of boys in the four sciences of this study has exceeded the number of girls in the sample area. The percent of boys taking general science, biology, and chemistry rose slowly but steadily; while the percent taking physics rose sharply until 1954, but after that year declined. Specifically, the percents were the following:

Very little change has occurred over the past 6 years in the average size of science classes. For each of four sciences the size in the 1958 sample was as follows: