I miss my old schedule of 8/6. I loved the time off, but like you I had trouble figuring out what to do with the time. I ended up sleeping as late as I could then I went to the gym everyday that I was home. That many days in a row allows for a pretty good workout routine if you enjoy the gym.
As for a part time job, I had always planned on becoming a substitute teacher. My city pays subs about $100 a day and there is always a demand for them. You can work on the days you want and take off the others. Unfortunately, I never signed up while I had the time, and now my schedule is awful at the regionals.
Good luck with it. Let us know if you come up with something good.