Ah, yes... I see what you are doing here... you are taking the worst examples of human injustice and using them to justify the outrageousness of a school taking steps to keep the children safe from the threat of arson, or suggesting that the 13 cops charged with murder (in 2013) or the 2,500 claims of brutality, out of the 1.5 million arrests (that's 0.0016%) is somehow equivalent to jack booted Nazis marching through streets rounding up Jews. I suspect that teaching 10 year old's that every cop is a potential Nazi will not serve him or her well as they try to make their way in the world.
RE: How to teach my 10yr old to put his hands up