I would call and ask some of the ambulance services in your area if they have, or know of any explorer posts for people interested in emergency medical services.
I also remember watching a documentary a few years ago about a volunteer ambulance service that had mostly teenagers working as EMT's, along with an adult medic or EMT supervising them.
I ould be wrong but I think the name was Teanaulk (not sure of spelling)ambulance or rescue squad, and they were located in New Jersey