To operate a commercial motor vehicle in Massachusetts, you must first obtain a commercial learner’s permit. You will have to take additional tests to get your permit, depending on which class of driver's license and endorsements you need.
All Commercial Driver's License (CDL) holders must tell the Registry of Motor Vehicles (RMV) if they plan to operate within the state or outside of the state, and if they're required to have a medical certificate.
To operate a school bus in Massachusetts, you need a Commercial Driver's License (CDL) with a Passenger (P) Endorsement and a School Bus (S) Endorsement. You also need a school bus driver certificate from the Department of Public Utilities (DPU).