A good way to have fun while working your brain at the same time? Video games, they will keep you occupied for hours and every second of that time your mind will be at work learning. There are an infinite amount of them with new ones being made everyday, they are all different from each other and no two are alike. Videos games are also a really good social experience and a great way to make new friends. Most games are cheap and a lot are free so you really have nothing to lose.
It's not the best as I threw it together on the spot. I would change a few thing so that way if your teacher checks it for plagiarism it will come back original.