I think the metronome clicking was heavy-handed. In the scene, you have people moving around in the room, Sam getting hysterical, Ryder doing his calling, yet nobody jumps to grab the metronome and silence it.
I also wonder about how the shot was noticed. It seemed like everyone in the entire school heard it. It doesn't seem possible with a school that size.
I also thought the tableaux was sloppily done. The mother is just standing there crying over her pot of spaghetti? Does she make an attempt to hide? And I knew who did it about 5 seconds into the shooting because everyone was being shown but Sue and Becky. Didn't anyone have any concern for Becky's safety?
And why was Tina not in class? What did she do to offend Ryan Murphy that she wasn't in the scene. And whatever happened to Sugar and the kid with the long hair?
And in classic form of Glee episodes past, why didn't Rachel, Kurt, Finn, Puck, Santana, Mercedes, Quinn and Mike come flying in to hug the group and sing a song with them?
If anyone ever tells you that you put too much Parmesan cheese on your pasta, stop talking to them. You don't need that kind of negativity in your life.