This research brief examines high school students' coursetaking in STEM (science, technology, engineering, and mathematics) subjects. As technical and scientific innovation increasingly drives the global economy, educators and experts in technical fields have expressed concern about the academic preparation of U.S. students in STEM fields. Using data from the National Assessment of Educational Progress High School Transcript Study [HSTS], this brief compares STEM coursetaking among the 2005 HSTS cohort with that of the 1990 and 2000 HSTS cohorts. Average credits earned in three broad STEM categories are examined along with and the percentage of graduates who earned credits in 12 specific STEM while in high school. Results indicate that graduates from the class of 2005 earned more credits in each of three STEM course categories (advanced mathematics, advanced science and engineering, and STEM-related technical courses) than did their 1990 peers. In 10 out of 12 specific STEM courses, the percentage of graduates who earned credits grew from 1990 to 2005. Gains were generally found across gender, racial/ethnic groups, and community types, but gaps between groups remained largely unchanged. (Contains 1 footnotes, 6 tables, and 11 figures.) [This publication was prepared by MPR Associates, Inc. with support from the National Assessment of Educational Progress Education Statistics Service Institute.]