Any fun summertime activities?

I have recently graduated Middle School and really yearn for a memorable summer. I live in NYC and although there are a lot of attractions I can't really choose. Can anyone please help me find certian places to visit or ideas on how my friends and I can occupy ourselves? I'm not on a tight budget but I wouldn't want to spend a lot of money on anything really, I have a few ideas up my sleeve but I definitley don't want to be bored until they come.