I am surprised that this has not happened before now. The President of the United States should be in schools. I see his mug everyday when I walk in my command...
I hear ya.
I think a fair argument could be made that it is reasonable in a military setting. The President, whoever that may be, has Constitutional authority as Commander-in-Chief of the military. I see no parallel for leadership of local educational districts, however. That has always been a matter of local control. There is no federal authority (yet). So, for now, I’d prefer not to see pictures of sitting Presidents in classrooms. An exception might be for historical recognition. IIRC, many of my classrooms back in the ‘50s and early ‘60s had portraits of Washington and Jefferson, but I always interpreted that in the historical context.