The school is insisting the child use a different name since their weapons policy bars any instrument that looks like a weapon.
This must not happen.
At first I was going to suggest something like the Hawaiian Good Luck Wave, but realized the name would be used by school staff when communicating to him.
Therefore, a list of names school may let him use: WeAreABunchofFreakingIdiots, or WhoeverThoughtofThisShouldSucktheSweatOffHis$Bodypart, or UsingThisSignJustProvesZeroToleranceDoesNothingToSavetheChildren.
And every teacher, administrator, aide, cafeteria worker, janitor, bus driver, and crossing guard (did I leave anybody out?) must be taught how to sign his School Name and be tested monthly on doing it properly.
stay safe.
PS - Choice #2 has some real promise in providing returns under Zero Tolerance. Please vote for Choice #2.