Petition against religious schools in the UK

This petition of the Prime Minister reads as follows:

We the undersigned petition the Prime Minister to Abolish all faith schools and prohibit the teaching of creationism and other religious mythology in all UK schools.

Faith schools remove the rights of children to choose their own religious, philosophical and ethical beliefs. They also sanction ethnic segregation and create tension and divisiveness within society. Schools should be places where children are given a free education, not centres for indoctrination. Creationism and other religious myths should not be taught as fact regardless of the funding status of a school. Abolishing faith schools will provide children with more freedom of choice and help to promote a fully multi-cultural, peaceful society.

Good on them. I've often wondered how people get away with denying children accurate science education. If my kid misses science class for too many days he can be deemed truant and I can be charged with a crime, but if I keep him out altogether because I prefer to teach him fairy tales that's...OK? Because religious nonsense is better protected in our culture than other forms of nonsense? What if I decide that the proper education for my son involves a curriculum that teaches, for example, that spring replaces winter when Persephone returns from the underworld to visit her mother? How is that any crazier than teaching Christian creationism as fact?