I have $300 to my name (US)

I’m in college right now and it’s in the middle of nowhere. I’m a stage hand for a show choir so I’m stuck on campus all week. I had like $3500 after I graduated last year and I worked at a radio station in the summer, but once school started income just kinda shut off besides pocket change I’d get from doing little part time stuff on weekends.

When this summer comes, I’ve got an arborist job lined up, and I can still do radio on the side. However, that’s 2 months from now. What can I do between now and May to make some money? I still have the radio job and grass is gonna start growing soon so there’s that. How old do you have to be to donate plasma, and how badly do I need plasma? (I’m 19 btw)