WHAT FACTORS MIGHT CONTRIBUTE TO THE FINDING THAT THE INTERNATIONAL STANDING OF U.S. STUDENTS IS STRONGER IN SCIENCE THAN IN MATHEMATICS?
In Chapter 1, we have seen that at both the fourth and eighth grades, our international standing is stronger in science than it is in mathematics. In science, our students are above the international average at both grade levels. Among the 26 nations that participated in TIMSS at both the fourth and eighth grades, only one nation outperforms us in science at the fourth grade, and 8 nations outperform us at the eighth grade. In mathematics, our students are above the international average at the fourth grade and below it at the eighth grade. Seven nations outperform us in mathematics at the fourth grade and 13 nations outperform us at the eighth grade.
Logically, if we are to suggest that any particular factor may be related to our students' stronger international standing in science than in mathematics, that factor should be present in different amounts in mathematics and science, relative to the international average. This difference should also be found at both the fourth and eighth grades.
Further analyses will allow more in-depth comparisons of these types. Based on the data available at this time, it is not always possible to compare background characteristics of U.S. eighth-grade education to the international average. Currently available TIMSS data allow within-U.S. comparison of differences between fourth-grade mathematics and science for only a few background factors. At the time of these initial analyses, comparable data for the eighth grade are not yet available. Later analyses will allow for much deeper investigation of these subjects.
In mathematics, according to expert judgment concerning the number of topics officially intended in mathematics, the U.S. intended curriculum includes more topics than the international average at both the grades, fourth and eighth. In science, the number of topics in the U.S. intended curriculum is somewhat below the international average at grade 4, and close to the international average at grade 8. If all grade levels between one and eight are examined, science appears closer to the international average than mathematics. Thus, the U.S. intended curriculum may be more focused in science than in mathematics.
When asked what they actually teach, teachers of 73 percent of U.S. fourth-grade students report teaching fewer than 17 mathematics topic areas per year. In science, the comparable figure is 50 percent. At the eighth grade, mathematics teachers of 55 percent of U.S. students teach less than 17 topics per year, in comparison to science teachers of 75 percent of U.S. students. Figure 11 shows these findings. At this time, only U.S. data are available on the implemented curriculum. Therefore, we cannot compare these U.S. findings to those of other countries.
In summary, evidence concerning curriculum focus is mixed. Relative to other countries, the U.S. intended curriculum is more focused in science than in mathematics at both the fourth and eighth grades.
As described above, U.S. fourth graders spend more time in class per week learning mathematics than learning science. In mathematics, U.S. fourth graders receive 4.2 hours per week of instruction and 2.7 hours per week in science. In both subjects, U.S. fourth graders receive more instruction per week than the international average. However, relative to the international average, U.S. fourth graders receive considerably more additional science instruction than mathematics instruction. U.S. fourth graders receive 48 minutes more science instruction per week than the international average, and 18 minutes more mathematics instruction per week than the international average.
Initial analyses do not provide comparable information for the eighth grade in both subjects, nor do they provide an estimate of total amount of class time per year, taking into account the number of weeks in the school year.
At the fourth grade, there is usually no difference between class sizes in mathematics and science because most students in the U.S. and in the majority of TIMSS countries study mathematics and science in the same class from the same teacher.
Evidence concerning teacher experience is mixed. Both absolutely, and compared with the international average, U.S. eighth graders are less likely to have teachers with more than 10 years of experience in science than in mathematics. In the U.S., 52 percent of eighth-grade students have science teachers with more than 10 years of experience, compared with the international average of 62 percent. In mathematics, 62 percent of U.S. students have teachers with more than 10 years of experience, which is not significantly different from the international average.
At the fourth grade, in the U.S. and most countries, teachers have had the same amount of mathematics and science teaching experience because the same teacher teaches both subjects.
Approximately equal percentages of U.S. students have positive attitudes toward mathematics as have positive attitudes toward science. In both subjects, at both the fourth and eighth grades, a majority of students report that they like these subjects and feel that they usually do well in them. In both subjects, the percentage of U.S. students who express positive attitudes is similar to the international average except in eighth-grade mathematics where the percentage of U.S. students who liked the subject was above the international average.
Evidence concerning why the international standing of U.S. students is stronger in science than in mathematics is inconclusive and incomplete. Further analyses will shed more light on this question. For most of the factors for which data are currently available, there is no difference between mathematics and science, or evidence from the fourth and eighth grades is mixed. The only factor among those reviewed here that exhibits a difference between mathematics and science is:
- Compared with the international average, U.S. fourth graders receive considerably more additional instruction per week in science than in mathematics.
However, it is not clear if this difference is also characteristic of the eighth grade, or if it represents more total class time per year. Therefore, caution should be used in assuming that it contributes strongly to U.S. students' stronger performance in science than in mathematics.