Courses numbered 100-299 are called lower division courses and are usually considered entry-level courses (appropriate if you are a freshman or sophomore or if you are beginning coursework in a new discipline). Courses numbered 300-499 are called upper division courses and are usually appropriate if you are a junior or senior or if you have prior coursework in the discipline. Courses numbered 99 or lower are not applicable to graduation requirements. Courses numbered 500 or higher are courses offered in graduate programs and usually not taken if you are an undergraduate.