(For reference, I'm 17 and am responding as such)
Cleaning, studying, sporting activites.
While there are people who do these things, they prove to be on the whole uncommon activities. If these things are being done it is likely they don't consider the time they do these things with 'free time'.
We prefer to relax, be unbothered, and see what's going on on Y0uTube or social media, or just watch TV.