This happened to my son's 8th grade trip to DC in Feb. They were on US Airways from SFO and US bumped a number of kids from one of the two flights. As as aside, it most probably wasn't the school that made the flight bookings (either in my son's case or the case in point here). These trips to DC tend to get organized by specialist companies who handle all the logistics for the trip including all the flight arrangements. If that's what happened here it's more likely than not that the school isn't directly to blame, it's on both the trip planner and the airline - comments about the irresponsible principals/teachers etc are probably off-base. Anyway, nothing wrong with AA overbooking a flight, but there's everything wrong with AA accepting a group booking involving so many minors and not itself ensuring that things didn't turn out the way they did. One PNR with so many passengers (which may well have been the issue here) ought to have stuck out and raised a few flags pre-departure.