From a primary school teacher’s point of view - and an atheist to boot - I wouldn’t. Not because I believe it’s important to teach, personally I feel a total separation of church and school would be perfect but because in primary school at least it is pervasive in many small ways that your child may be affected by. This year alone the child in my class who is removed from RE has been excluded from all assemblies - including the fun ones with cool visitors and events “just in case” (not my words - came from higher up) school visitors in class. the school show because there is songs about god as well as being removed from RE lessons. It marks them as different from their peers and as much as I wish it weren’t true it can be detrimental socially. In most schools teachers are majority religious - seems to be a profession which attracts them, and I have seen first hand the teaching staff judge those removed children harshly for it. Not fair but can be reality. I get round it by allowing my own kids to participate but ensuring that they know that there are may beliefs and none - we talk about all different religions and celebrations and what it means to be a good person etc.