You can’t say someone is ‘too smart’. The world needs intelligent people to help make changes and solve problems, big and small. Yes, she might be smarter than you but that’s no reason to try and change her.
If you become more confident, you won’t feel threatened by her smartness. And if your friends are teasing you, just ignore them.
You and I both know the only way you can get to know her better is to talk with her. So I suggest you start reading out loud to get used to the sound of your own voice and do the other things I suggest in this article.
They really are remedies for shyness so give them a try and see how you go. I’m expecting you’ll be saying hi and asking her a few questions before long. Once you gain the confidence to start talking with her, it will become easier and there will be no stopping you.