Data Structures
Roles
Stuff like "staff" or "keyholder" or "public"
Clearances
Things the person is considered allowed to do / teach
Competencies
Stuff a person has learned which allows them to take advanced stuff or train an apparatus
Users
Actual human beings
Class Descriptions
Where classes are defined, but not scheduled
Is there any reason private lessons shouldn't just be a type of class?
Class Schedules
Where classes are scheduled
Class Categories
The types of classes there are (trampoline, intro, aerial, workshop)
Resources
Locations, equipment, etc
Transactions
When people buy/use stuff