re: "it seems to me that any degree of leftist extreme sentiment is allowed to be posted in edu institutions"

I can only speak from experience, but when I was in HS, no controversial expressions of any kind were permitted. And on one would dream of publishing anything in a teacher's classroom without permission.

We were once hauled before the principal for posting an extremely well done rendition of God stretching out his hand to Adam (ala Sistine chapel) only with a snocone in his hand. I forget exactly what the caption said, but it was an inducement to buy snocones as part of an art club fundraiser. Of course, the artwork was destroyed. It was posted outdoors in a public area and covered nothing but the retaining wall (to a higher level of the campus).

Another time, on our annual "beat rival day" we posted the slogan: "Better dead than red." (rival's school color was red). Same result.

And we took this treatment like the mature, HS students that we were.

This kid has the Republican whine down perfectly.