Just a tip that I learned from our plane ride last year.... Don't let your child wear light-up shoes! My son (who was then 3) was wearing light-up sneakers and set off the alarm (of course, I didn't even think of this as the reason at the time...) They took myself and my son aside to search him, however they would not let him sit on my lap or hold me. He was so scared!!! They patted him down all over, ran the scanner over him, and checked all his buttons, pockets, etc... and it kept beeping. It was not a pleasant experience for him. Needless to say, it was his shoes that kept making the scanner beep. They thoroughly checked his shoes since the batteries were not removable, and let us go. So parents out there, leave the light-up shoes at home!!!!
Jen