Below, you'll find various resources you may need as a volunteer, or if you'd like to research your options on other sites. I've also included a spreadsheet for high school students to compare different colleges as they begin to apply, just because I found it helpful.
This website takes into account what you love and have the bandwidth for in a very detailed way. Just put in your goals an receive a list of recommendations!
Idealist works much like the other sites on this list, but it uniquely provides opportunities for anything from jobs to one-off events.