ARLINGTON - High school students who study a few science topics in depth have an advantage in college science courses over those whose high school classes spent less time on more topics, according to a recent study.
Marc S. Schwartz, an education professor and director of the Southwest Center for Mind, Brain and Education at The University of Texas at Arlington, co-authored the study with Philip M. Sadler and Gerhard Sonnert of the Harvard-Smithsonian Center for Astrophysics and Robert H. Tai of the Curry School of Education at the University of Virginia.
"There are very few empirical studies on this topic, but it has a long history of debate," Schwartz said.
"Many teachers and parents want every textbook chapter covered in an attempt to prepare students for college," Sadler said, "but we found hard evidence that those teaching a few key topics are using the very best strategy."
The study "Depth Versus Breadth: How Content Coverage in High School Science Courses Relates to Later Success in College Science Coursework" relates the performance of college students in introductory science courses to the amount of content covered in their high school science courses. It will appear in the July 2009 print edition of Science Education and is available online.
The study included 8,310 students in introductory biology, chemistry or physics courses in 55 randomly chosen four-year colleges and universities in the United States. Researchers examined college students in their first, introductory college science course for the study because their high school experience would be relatively fresh.
Students who reported covering at least one major topic in depth in high school, such as cell biology, for a month or longer were found to earn higher grades in college science courses than students who reported covering more topics in the same time period. Overall, courses that concentrated on mastery appear to have twice the impact of those that cover every major topic. The study explored differences between science disciplines, teacher decisions about classroom activities, and out-of-class projects and homework. The researchers carefully controlled for differences in student backgrounds.
"In general, the positive finding was less about which topic to teach in depth, but to focus deeply on some part of the curriculum," Schwartz said.
The study points out that standardized testing, which seeks to measure overall knowledge in an entire discipline, may miss capturing a students' high level of mastery in a few key science topics. Teachers who "teach to the test" may not be optimizing their students' chance of success in college science courses, Schwartz said.
The study was part of the Factors Influencing College Science Success study, which is funded by the National Science Foundation.
The University of Texas at Arlington is an Equal Opportunity and Affirmative Action employer.