door "finally" opening needs an earlier sign that it had been stuck. that's a good example of showing description's cause and effect flow better, and you can do it different ways. if he sees the door stick we get the implication of "great start, even the bus doors hate him"; if all he sees is the doors not opening he might wonder if the driver's not sure he belongs. or he might not be watching the doors, just stealing a moment to look at the kids, and that turns into several seconds before he's pulled out it by the sound of the doors.
this is a well-chosen opening scene that moves 