Faiths which require more intensive teaching are taught outside school.
Parents, even of primary children have the right to withdraw children from all or part of RE. (Though not RSE). When some of our parents learned that their children would be taught about Islam, a group spoke to the head about withdrawing the children.
Having looked at and discussed with the head, what would be taught in the syllabus and how it would be taught, (and some felt they had learned something new themselves) they decided against withdrawal, but they had the choice.
Don’t you think it is important for children to know about other’s faiths and way of life?
Nowadays, in state primary schools there is no prerequisite for a teacher teaching RE to have a particular faith or even a faith at all. RE in the curriculum means children hear about different faiths and beliefs, rather than religion being secretive and fed by rumours from people whose only knowledge comes from the media.
It means they learn about how different beliefs mean different ways of life for others, like the wearing of turbans or different clothing, fasting, food, etc.
Similarly, integrating SEND children into school where possible means children are aware of the different problems faced by others.
Mostly, when faith schools are the only school available in small villages, it is because the church saw a need for a school in that area and it has continued to be called by the original name. Some faith schools receive funding from the church as well as from the state.