As long as it doesn’t open the door for Islamic radicals to start demanding the teaching of Islam, I personally have no problem with crucifixes in schools. The EU is way ahead of us in terms of Muslims integrating into the population and I’m always wary of giving them a loophole to preach their “religion of peace”. Anything that can be done to keep Sharia law out of Western Civilization is a small price to pay.
I would never consider hanging a crucifix in a classroom, a "small price to pay". My daughter spent most of her years in government "secular" classrooms. Recently, she switched to a Catholic college. Her first comment? "They have crucifixes in all the classrooms." And she meant it as a sort of comfort to see her Lord and Savior's presence in a learning environment. Ditto for me when I underwent major surgery a few years ago in a Catholic hospital. It brings great comfort to look up at the wall and see Christ.
As for keeping sharia law out of western civilization, as a nation, we still have a formidable christian presence that is willing to fight to preserve our christian heritage. It is now too late for Britain.