Brass is the thinnest pool on Google Maps. Below are the few studios that explicitly name trumpet — most trumpet teaching happens within multi-instrument schools or conservatory prep.
Real Boston-area teachers — dedicated private studios where available, plus the multi-instrument schools that have trumpet on staff.
For trumpet specifically, the conservatory and ensemble programs (NEC Prep, Boston Conservatory at Berklee, Longy, Rivers School Conservatory, Berklee for jazz) are stronger sources than Google Maps.
Trial class included with first enrollment — no risk, no payment until you're sure.