Similar conclusions have been drawn by other researchers. The dynamics that underlie students choices are complex. The courses students take reflect personal preferences as well as contextual factors, including offerings that are available and practices and policies that determine student access. The configuration of courses available in a school delimits the courses students can take and thus what they learn. The curriculum can be comprised largely of basic or survey courses or, alternatively, can include a substantial number of advanced courses.
Some courses play a special role as gatekeepers.
A student who takes algebra in eighth grade can readily take a full mathematics curriculum in high school. Advanced courses and gatekeeper courses are not equally available in all schools or to all groups of students. Calculus, a gatekeeper course, lies at the extreme. Even a school with extensive course offerings may engage in practices that deny access to some groups of students. Graduation requirements are associated with course taking generally.