Cross-domain analysis was used to examine changes in two attitudinal dimensions: students' attitudes towards science and attitudes about the utility of science over the middle school and high school years. A sample of 444 students was selected from the Longitudinal Study of American Youth. The results show that the overall trend for students' attitudes about the utility of science is positive; however, attitudes towards science decline over the middle school and high school years. Important time-varying predictors of both attitudes include science self-concept, peer attitudes, teacher encouragement of science, and, to a lesser extent, student participation in science activities. (Contains 5 tables and 1 figure.)