Two twenty-level courses are required for the major, one from the set 22, 23, 24, 25 and one from the set 21, 26, 28. Courses numbered in the 20’s are open enrollment (though sometimes limited by available seating), courses designed to provide broad coverage of a particular area of Psychology. Complete descriptions of these courses are available in the ORC. These courses usually have Psychology 1 or 6 as a prerequisite, but in some cases, alternate prerequisites are possible. All courses numbered 20 or above carry major credit. Most of the 20-level courses are taught in a lecture format. Enrollments in such courses over the past few years have ranged from 60-150. In general these courses use the Registrar's priority system as follows: Senior majors, junior majors, senior minors, junior minors, sophomores, other seniors, other juniors and first-year students. As much as is possible, 20 level courses are offered every year, and in the same term each year.