There are some things I need not tell you to put in your bag: shoes, any cover-ups (skirts, shorts, shirts...), etc. Legwarmers are good incase it's a bit cold. There are lots of other essential items that often come in handy. It's a GREAT idea to always keep a water bottle in there. That's probably one of the most important things. Water keeps you hydrated and provides you with the energy needed to get through those long classes. Also, you should keep extra bobby pins, hair nets and hair ties in case your hair falls out or someone needs to borrow some. Ribbons and flowers are nice decorations for your hair. It's also a good idea to keep some deodarent in there, too. Don't forget any toe treatments, such as New Skin, Band-Aids, toe-pads and tape. You should keep your pointe shoes in a mesh sack tied to the outside of your bag so they can air out. Other miscellaneous things you may need are tampons (or whatever you use) for those days when you don't know it's coming, and some money, just in case.