Fun things for teens to do in Atlanta Georgia for a week?

I’m helping my friend out again with her school work. This time she needs to find interesting things for a group of four 17–18 year olds to do in Atlanta Georgia.
The project assumes they are capable of getting around (have cars, etc.) and have a generous budget (they don’t have to spend it all, but they can’t occupy their entire trip with free things). The budget is around $3,000 (thus far, assuming her group mates don’t spend the rest of the budget on stupid, fancy hotels).
The activities have to be “school appropriate.” I haven’t the slightest idea what the means, because she attends a California High School, and apparently, everything is okay in those schools. (That last sentence is just venting. I hate that school system out there).
She’s got travel packets and things, but I’m just wondering if you guys know of any “secret” things they can do that will make their project stand out. Like a cool park that isn’t on any map, or tourist pamphlet, or a really amazing movie theater that only locals would know about. The kicker is, it has to be real, because she needs to show prices and travel time from where they are staying, etc.