You'll get a combination lock if you buy your lock from the school. You can also buy your lock elsewhere, but if you forget the key or combination, the teacher can't help you. If you buy it from the school, the teacher will have a master key that can open it, if not, you're busted for the day. I bought a lock from the school, but kinda use it as a toy at home. I can't help it though, it works for one!
Well, that's all I really have to say. Hope you have a good day!