I read your tweet : Do you check the money that you send with your kid to pay for lunch? Better start! I think that these folks need to know that punishing this child is ridiculous!
Not long ago someone paid a fine or purchased books at the library and used a counterfeit $5. When I tried to deposit the $5 the bank pulled it. I had no idea. The money counter picked up the counterfeit bill. A counterfeit bill is not obvious. So that poor kid should not have been penalized and suspended.