It must have been Rookie Week for school bus drivers here in Springfield. I was riding a wide lane (probably 16 feet) approaching a high school and an intersection. I knew a school bus had been approaching from behind from my sunglasses-mounted mirror. Heard the engine rev, the bus accelerates and speeds past me, cuts in front of me and over right into the pull-in bus parking lane, and he had to hammer the brakes to get that thing stopped in time. Then he put out the STOP arm for good measure, making me stop in the lane beside him.
Hopefully there was a supervisor or someone who saw it all to give some kind words of improvement to the driver (no kids on board, school is not in session yet). Dude coulda slowed and gotten the same place in 5-10 extra seconds without hammering the pedals.
It wasn't a dangerous pass in that he never got close to hitting me; it was just particularly inartful.