play in preparing students to succeed in undergraduate science education. However, one study is available (Sadler and Tai, 2001). The authors surveyed nearly 2,000 undergraduate physics students at public and private institutions and compared their undergraduate physics grades with their high school physics experiences. The analysis of the survey findings indicates that, when demographic factors were controlled, taking a high school physics course had a modest positive effect on undergraduate physics grades.
The researchers also found that students who took high school physics courses that spent more time addressing fewer topics in depth (including fewer concepts, topics, and laboratory activities) had higher undergraduate physics grades than students whose high school physics courses covered more topics in less depth. The authors suggest that high school physics teachers should concentrate on a limited set of topics related to mechanics and include laboratory experiences carefully chosen to reflect those topics. They note, “Doing fewer lab experiments can be very effective if those performed relate to critical issues and students have the time to pursue them fully” (Sadler and Tai, 2001, p. 126). These findings suggest that laboratory experiences may be more effective in supporting student learning when they are integrated into the stream of science instruction, as we discuss further in Chapter 3.
Trends in public understanding of science and science achievement are influenced by larger changes in the U.S. education system. Rising immigration—the total immigrant population of the U.S. nearly tripled from 1970 to 2000—and the baby boom echo—the 25 percent increase in the number of annual births that began in the mid-1970s and peaked in 1990—are boosting school enrollment. After declining during the 1970s and early 1980s, enrollment in public schools increased in the latter part of the 1980s and the 1990s, reaching an estimated 48.0 million in 2003 (National Center for Education Statistics, 2004d).
With rising enrollments, some science teachers face large classes. In California, total statewide enrollment in kindergarten through 12th grade grew from 5.2 million in 1992-1993 to 6.3 million in 2003-2004 (California Education Data Partnership, 2005). In recent years, the average size of science classes grew from 29.3 students in 2000-2001 to 30.1 students in 2003-2004 (California Education Data Partnership 2005).2
California and other states also report pupil-teacher ratios. This ratio is different from average class size because it is the number of pupils per full-time-equivalent teacher, including teachers who are not in the regular classroom. The pupil-teacher ratio in California high schools declined slightly from 24.5 in 1992-1993 to 23.5 in 2003-2004 (California Education Data Partnership, 2005).