What could I do for my 13th birthday (Im a girl and I don't want to spend too much)?

My birthday is in july and I want to celebrate with just some of my close friends. Do you have any ideas of where we could go/what we could do? I am thinking maybe the beach or something involving makeup or a movie. (by the way, any fun movie ideas?) It is probably going to be hot out, so things involving water is going to be okay. but no pool! I want my birthday to be memorable and fun for everyone. A scavenger hunt would be a lot of fun... I am leaning away from a sleepover. and coed things are a no no. I am so excited! and thanks for your help! (But I don't want it to be an official party with gifts and stuff. just a fun get together type thing)