Massachusetts requires that vehicles stop for a bus that has flashing lights and an extended stop sign, when you are driving behind or toward the bus.
You may resume driving when the lights top flashing or the sign folds back in.
These rules apply to pupil transport vehicles—like vans, station wagons, or family sedans, that have flashing red lights and "SCHOOL BUS" signs on top.
Failing to stop or illegally passing a stopped school bus with flashing lights can result in $250 fine in Massachusetts, at minimum. A second offense by a fine of not less than $500.