You will still only be guaranteed 30 hours a week. Management varies implementation at different learning centers, but the corporate policies can be enforced so that you have to be available during all of their business hours, which can be from 7am-7pm on weekdays and some varying hours on weekends. The schedule changes week-to-week, so you will never know if you can schedule something in the afternoon or evening.
For the actual position: You will be expected to oversee students through their programs, manage their behaviors, throw parties, and meet with parents. Depending on the center, you may be over-scheduled, including filling in for other positions, and still expected to fulfill all duties on an hourly rate. They will track your paperwork online and send a report to your manager if your paperwork is not completed in the way they expect.