@OsuldBergland,
It is helpful if we knew your location - but to think of common summer jobs think of things in your area that are open only during the summer or have most of their business during the summer. Things like summer recreation. My daughter is applying for a camp counselor job - think of day camp not overnight unless you happen to be near one.
Many YMCAs, town recreation centers and similar have summer camps and look to hire people just during that time. How about any places like seasonal ice cream stands, mini golf, go-carts type places.
You could also reach out to a temporary employment agency - they could assign you a job from a few days, to a week, a month or the entire summer. I once obtained a job through a temp agency that was supposed to be very short-term and I did a good enough job, they kept me through the entire summer.