As does its Christian equivalent, Lent.
Good point. What sort of Lent guidelines do you think teachers would need in order to avoid problems with their students? How does Lent affect a typical Catholic student's school day?
As I see it, these guidelines are concerned with issues where there is a real lack of familiarity and understanding. I don't think someone should feel "left out" if another holiday isn't discussed. The obvious explanation is that there's not a similar need for guidelines about a holiday if it has less impact on student life in school hours and it's something the teachers (who are much more likely to be Catholic and have Catholic friends than to be Muslim or to have Muslim friends) would know about.
I don't think you should feel victimized or left out by these guidelines. I don't see what harm they do. If there were a real need to educate teachers about how students celebrate Christmas, it would be done.