Do you have any ideas for a 15th birthday party?

Hi my name is Bree and I am turning fifteen on Valentines Day. My school is giving us a four day weekend because of president’s day. On friday I am going on a school trip snowboarding with some friends on friday the 12th. But I don’t have any ideas for my birthday on that Sunday two days after the snowboarding trip and we have no school on monday or tuesday. If you have any ideas please respond. Also i would like to invite a few guy friends. My budget is $650 at most. Thanks :)