I was lucky... I went to a high-school that was full of nerds. We had computers, electronics labs, great science teachers. We competed in competitions with other schools. Nobody even thought twice about anything you bring in. The teachers knew who you were.... Nerds were not "socially isolated loners" because there were lots of them who shared interests. We had a math club, science club, etc...
I don't know anything about the school that Ahmed attended, but I wonder if not one teacher or student or anyone else surrounding this boy not stand up for his character? Not say to anyone that they know him and that he is completely in character, showing off one of his nerdy creations? Could nobody explain or at least listen to this boy explain or demonstrate this electronic device (which seems to have no explosive material in it whatsoever, just circuits)? Could not anyone figure this out before police showed up and arrested him and took him away in hand-cuffs.... With an awesome photo to boot!?!?!
Come on! This didn't happen in 2 seconds. They must have had at least 10-20 minutes or longer before police arrived to sit and talk and get other people involved. Or did they just sound the "panic button" and evacuate the entire class and school and run away from him?