How flexible should you be for ballet?

No one's going to throw you out of ballet class for not being flexible, but the more flexible you are, the more moves and positions you'll be able to do. And then it will be more fun for you! Talk to your teacher for ways to improve your flexibility. It'll take a long time, and you'll probably have to work at it a little every day. Yoga classes and Pilates can help develop your flexibility, too.