Absolutely inexcusable.

[Paladin]

Those who are responsible for this travesty need to be publicly exposed and then punished---firings, expulsions, whatever is the most effective.

The significance of "Arbeit Mach Frei" isn't some obscure fact that requires a background in WWII history to recognize. The term has appeared in well-known books and films dealing with The Holocaust for many years. Imagine being someone who lost relatives in those death camps, seeing those words at a religious school's holiday parade. Just inexcusable.