No school buses, except twinkie school buses, (the small gasoline engine buses) have a drivers side door. The door handle on the full size buses, actually a knob to open and close the door with air pressure is pulled out to the open position and a lever above the door is pushed to the open (vs closed) position then the door can be moved manually.
johnpowell must be very fit, I have never found a new or old school bus door you get open or close w/o the air being bypassed. You may push then a little, but will open back up when you take the pressure off.