Bro i ain't messing around you look like charlie brown came in to your town shot everyone down
turn that smile to a frown cause you a clown man wheres my first place crown
got so much money in my bank account i started hear sounds blood everywhere in the towns i told them not to mess with me yeah fighting is my number one key

This is all you, but i can give you some topics that you could try. if it rained when you want to do something outdoors, it 'limits' that human activity. maybe you want to do an experiment that goes throughout the whole year and you have to have above freezing the entire year. this 'limits' your activity. i thought of those just off of the top of my head. something that gets to me that might be getting to you is you are thinking too hard about what to do. think simply, and if it is too simple, then bump it up just a little bit.