Double Violation

[BigJoe]

Chuck nailed this one. I don't think they could have moved at the same time. One of the players initiated the violation and that is the one to penalize. If it is the shooting team cancel the shot and non-shooting team gets the ball OOB at the endline if it is a bonus situation. For two shots, shoot the second free throw and continue the game. If the defending team initiates the violation, hold your whistle and award another throw if the free throw is no good.
An aside to the situation, just because you are "only" a middle school official doesn't mean that you are excused from having minimal rules knowledge. In my opinion you have more unusual situations at this level than any other. Spending time with your rules and case books is a good way to spend time while watching t.v. at night. The fact that you are on this forum is a step in the right direction as well. When reading this forum it is a good idea to have your books next to the computer so you can look up each of these situations as they are presented. Eventually, you will have the benefit of everyones odd situations so when they happen to you, you will be ready with the proper calls.
Sorry for the sermon, but I want everyone to be the best officials they can possibly be.