Columbia High School operates on a 5 Period Day/Trimester schedule. Most days classes run from 8:15 am to 3:10 pm, but there are a variety of other bell schedules used from time to time during the year, including Early Release schedules (used most Mondays), a 12:20 Release (used before some holidays and on parent-teacher conference days), a 2-Hour Late start (used due to inclement weather) and an Assembly Schedule (used when school-wide events are planned during a regular schedule day).