There are three different types of hangouts that your students can call home.

Nerd Hangouts: Gives a maximum of 3,500 coins per hour, holds 2 students.
Jock Hangouts: Gives a maximum of 2,000 coins per hour, holds 3 students.
Prep Hangouts: Gives a maximum of 1,000 coins per hour, holds 3 students.

Keep the Prep Hangouts to a minimum. A good combination is to have one Prep Hangout, three Nerd Hangouts and three Jock Hangouts to maximize coin production.