Changing class duration and frequency
Playing for a semester or partial year? When creating your class, use the “Game Duration” option to set your class duration and how many hours per week you see your students.
The game uses this info to determine how much XP your students should need to level up (their “level cap”) and how much AP they should regenerate each day at midnight. (You can find the "Game Duration" option in your class settings under the Advanced "Game Rules.")
You can learn more about adjusting the duration of a class and the effect on level cap here.