I thought I remembered pretty definitively during elementary school that there was like, a big red button next to the bus driver, that the kids were supposed to hit in an emergency, while you were supposed to also steer the bus and keep from crashing in the meantime. I could be wrong, though, or that could not be the case on public buses or buses of other types, I dunno.

Also, the buses did infamously have emergency exit doors, so you could always just open the emergency door in the back of the bus and jump out. That’s probably the other best option, relative to going over a cliff. Road rash can be pretty severe and bad, and you could get a concussion or snap your neck if you don’t know how to do the jump out sideways rolly thing. I dunno though, seems like you could do it probably.