There are 3 basic lengths of courses at Chelsea High School: quarter, semester, and full year.
- Quarter length courses end every quarter and need both quarter and final grades at the end of EVERY grading quarter for which they run.
- Semester 1 courses end at the end of quarter 2 and require both quarter and final grades at the end of quarter 2.
- Semester 2 AND full year courses end quarter 4 and require both quarter and final grades at the end of quarter 4.