Volunteer jobs for aspiring art therapist?

I'm interested in finding a volunteer job for the summer, just to have something to keep me on a schedule. Currently, I'm volunteering 3 days a week at a thrift store. I really love working and literally will do anything to make it so someone else doesn't have to do. I'm currently in high school and under 16, so that might put a hamper on my finding something. I would like to do something related to psychology or art. I'm just looking for something that i can do that also has to do with my interests. I'd like to still work at the thrift store, but also work somewhere else for the days I'm off (I have 4 free days a week!). I've checked volunteer match and my towns volunteer website, but there are no positions up relating to what I'd preferably like to do. Anyone got any suggestions? Thank you so much!