Turning 18 in 22 days and need ideas of what to do in Arizona!?

Im turning 18 in 22 days and i need some ideas of what to do. I live in the scorching heat of arizona. and i have always tried to have some friends come over and have a party but we always end up leaving and doing something else like just driving around so i need something to do with friends and i am one of the youngest out of my group of friends so if that helps with any more ideas. PLEASE! Give me some ideas im in need of them :) thank you <3