I always thought adventure was someone half a world away risking their life while eating bad food...

Anyway, while you're gathering gear you need to consider skills building (as already mentioned).

You need to be able to (short list)
- cook food
- do basic first aid
- pitch a shelter
- navigate
- purify water
- make fire reliably

This is a great time to make friends with the guy in your school who's stayed with scouting, or to go to the scout shop and pick up the Boy Scout Handbook. Prove to yourself, before you go, that you can do all the requirements for a First Class Scout. All the directions are in the Handbook. It will only take a couple weekends for a high school senior on his way to college (including doing some hiking and setting up camp), but it will help make sure you are set up to have a good time when you go this summer, and help you manage your risks.

Hope you have fun