Find an excuse to approach her. There is no need to have any good excuses, as long as it is an excuse. It's like "Hi, do you remember what the homework is?" or, "Hi, do you want to solve this problem with me?" As long as you break that layer of ice, you can start to become her friend. Again, no matter how you break the ice comma, as long as you don't threaten her, you don't act very proud. If you make yourself too embarrassed, don't worry-she will find it cute.