Summer fun ?

So I’m 17 living in Southern California and I want to do some really fun, stupid stuff with my friends this summer. So far we’ve only come up with

1) slide down giant blocks of ice on a hill

2)put nail polish remover on cotton balls, light them on fire, and throw them at each other

3)A game called ‘Wandering’

and that’s all. So I’m thinking like activities that would be a mix between any generic teen movie and any Jackass movies would be perfect for us lol. Do any of you have any ideas? :))