What affordable, fun things can a 16 yr old do in NYC with her friends (besides lunch/dinner)?

I'm trying to plan something for my cousin's birthday. She is 16, turning 17 in about 2 in a 1/2 weeks- and she wants to do something in New York City with a couple (about 9) of her friends, but I can't think of anything that would be FUN, AFFORDABLE, and DIFFERENT other than a typical movie and lunch/dinner. We already ruled out a play, and the movies... and I was thinking Seaport but there isn't a whole lot to do there, I want something where everyone can interact with each other. I was thinking maybe a club that has a teen night or something, but I'm pretty sure all the clubs in NYC are 18 and older. The only thing I have so far is food, and we are still debating on a restaurant lol...Any ideas?What affordable, fun things can a 16 yr old do in NYC with her friends (besides lunch/dinner)?
try a carnaval. pretty sure there would be one in NyWhat affordable, fun things can a 16 yr old do in NYC with her friends (besides lunch/dinner)?
go fishingWhat affordable, fun things can a 16 yr old do in NYC with her friends (besides lunch/dinner)?
you should all go shopping or something, or do sighteeing or something like that, go through central park or go on a mission like go through NYC and try to find 4 ex, a coffe shop with an orange couch or something strange that u can have fun doing . i guess that kind of weird but mabye it can give you an idea of some sort
How about the malls..you can sight see and eat at the same time....i like the palisade mall where they have the i max theater..then you have the rye play land where you can..eat , play and get on rides..there's this other place right after rye play land stop (when driving in car) you can eat there get on some rides..(.it's indoor)movie theater, bowling and Lot's of arcade games.....i forgot the name of the place..but it's a stop right after playland...it's nice over there too...and if you decide to go shopping you have the woodbury commons nice mall...but mostly all this u need a car....to take you'll and bring you'll, have fun...and be careful....NYC is a tough city....

dairy queen locations