I suppose essentially the point is that Islam should be treated equivalently to Christianity -- or at least, proportionately. Like it or not, people will insist on teaching religion in schools, and there are, what, about a couple of million Muslims in the UK? Not teaching it in schools at all in that context (again, if you allow that religious teaching is a part of education) seems bizarre.
The ideal is that religion should disappear largely from school life, although even then I suppose there's a case to be made that studying it at school would be a good counter to learning about Islam (and other religions) at home or at the respective place of worship. At least in the context of a school lesson it's much more open what is being taught, and why.