Asking about hours is confusing since different schools atribute the hours differently. I'd say if it's semesters, 4-5 classes. If it's quarters, take 3 classes.
I'd also like to take this time to say something to all the hopeful shiny faced freshman. Enjoy college! Don't kill yourself to get finished ASAP. Take your time. Fifth year is not uncommon in a lot of schools now. Six years is probably pushing it though. But do study and learn and get good grades. Also make sure to get crazy (safely). Take road trips. Get drunk (safely). Be impulsive! Then get back to the books.