This is the first part of a documentary of the most famous Russian ballet school.. there's a complete collection there in yahoo vids
And this is for those who said ballet dancers don't show their teeth when they smile haha! Its the black swan section from Swan Lake. You can see she uses different expressions to convey different feelings at diff moments.
When you do the esmeralda dance I taught you for the open house, its not the pure cheery smile you should have, but the playfully cheeky and teasing smile you can hear from the music. Here's a diff dance but exactly the kind of mood you should portray =P