You can't really expect 'books like that' not to exist, or that kids will never have access to them, even in some schools. I certainly don't think they belong in state schools, but with private schools it's rather more up to them. I don't think it's realistic to expect things like this will never be taught, and a serious attempt to stop it - say by criminalisation - would be an unacceptable infringement of freedom of thought.
However, I do think it's outrageous that the government should be lending it any support, even by something as passive as accrediting a course. Unfortunately, though, it's not the first time the government has lent support to creationists in the classroom.
BBC story