Religious education is mandatory in the UK. Getting rid of it altogether would be useful, and keeping a broad lesson incorporated into general studies about all religions would suffice.
However, this may be hard to acheive. So I propose that equal criticisms of all religions should be taught in schools. Religion is about not questioning and blind faith but school is about learning and questioning. If religion is to be taught in schools then both approaches should apply.
If children are to be taught about religions, with a strong bias towards christianity, then children should be equally taught why not to accept it as true without proof or evidence. Children should be taught how to use critical thinking and decide for themselves, looking at BOTH sides of the argument, whether religion is correct.
Religion in school teaches children to pick a religion, whilst nudging and pointing at christianity. It should also teach kids that they dont have to have a religion and that it is not necessarily correct.