The Lord is my headmaster

It's not that Elspeth and Alan Bright disapprove of the local schools. The decision to keep their children out of the education system has nothing to do with the state of the classrooms or the quality of teachers: it is, rather, a matter of religious principle. "Our feeling is that God has given the children to us to educate, not to give them into the care of people they know nothing about," says Mrs Bright. A former optician, she has been teaching her children at home for more than 10 years. The eldest has now started at sixth-form college – virtually his first experience of formal schooling. The other five are still learning around the kitchen table.

The Brights are part of a burgeoning Christian home-educating movement. Around 1,500 such families exist in the UK, and there could be many more. Most are evangelicals – some, like the Brights, align themselves with the evangelical wing of the Church of England, while many others are Nonconformist. They are joined by more than 100 Catholic families, who reject even the church schools as too liberal and secular.

The education the Bright children are getting – with the full knowledge and consent of the local education authority – is, not surprisingly, a religious one. All their lessons, from Bible study to chemistry, are tinged with religious doctrine. Maths, as Mrs Bright teaches it, is the study of divine laws; geography is the study of God's creation and how humans have abused it. "You don't have to try and bring God in," she explains. "He is there already." Scientific theories (including evolution) are tested against the authority of Scripture, and often found wanting.

In the last decade, the ranks of Christian home educators have swelled dramatically. A decade ago, there were probably only 20 to 30 such families, says a spokesman for Home Service, the chief lobby organisation for evangelical home educators. Today, Home Service is in regular contact with 420 families. "And we still get people writing to us, saying, 'We've been home educating for seven years and we've only just found out about you'," he says.

Not all home-educating families are religious, of course. Tens of thousands of parents educate their children at home, most because they think the schools are too bureaucratic, and don't deal adequately with bullying or learning difficulties. Christian home educators share these concerns, but have different motives. While secular parents object to the medium of instruction in the schools, religious parents find fault with the message – what Home Service calls the "humanistic modernism" of the national curriculum. To them, the schools are guilty of undermining religious truths and spreading lies about history, morality, evolution, and sexuality.

But parents wishing to instill a fundamentalist ideology in their children face a practical problem. Most educational books and CD-roms – not to mention most television programmes – hold to the same humanistic line that is pushed in the schools. To get round this, parents have to use books and syllabuses imported from America, where the Christian home-school movement is larger and better-organised.

It isn't an ideal solution, though. American religious textbooks don't prepare children for GCSEs, and often preach that the US has a special destiny, as Mrs Bright has discovered. "Some of the American Christian stuff makes me uncomfortable, because it goes on about how America is God's chosen land. It's very hard to swallow."

These parents face challenges that would daunt the most experienced teacher. As well as having to assemble a curriculum that satisfies divine commandments and Earthly examination boards, they must teach children of different ages and aptitudes. Can they possibly give their children a proper education?

Many professional educators don't think so. "There's no way that home education can substitute for an education in school," says a spokeswoman for the National Union of Teachers. "Education isn't just about learning to read and write. It's wider than that – it's about socialising children and encouraging them to develop their own independence. In addition, parents are not trained educators, and they can do as much damage as they can good. The child educated at home is actually having their education restricted."

Keith Porteous Wood, executive director of the National Secular Society, worries that Christian home educators are damaging their children's minds by force-feeding them religious dogma. "These poor children are going to be exposed to very extreme religious views, without any kind of outside or moderating influence," he says. "From our perspective, it's verging on intellectual abuse."

The Christian home educators dispute the charges. A child sitting in a classroom with 30 others of the same age is not getting a very accurate idea of what society is like, they point out. But the Christian educators freely admit that they are trying to keep control over what their children learn and who they interact with. For many, this is precisely the point of home education.

"It is an issue of control," says Graham Field, who with his wife, Tracy, has educated three children at home. "It isn't just the things you teach them; it's the whole environment. Children learn by example, and the kind of example they are set by other pupils – and even teachers, in some cases – is not one we would want them to have."

The Fields don't try to convince their children that their beliefs are uncontested, just that they are correct. As for the origin of species, Tracy Field says: "We teach what the Bible teaches, but we don't hide the theory of evolution from them."

In general, she tries to make her children aware of the world beyond the front door without allowing them to lose themselves in it. "There's a difference between innocence and naivete," she explains. "We want our children to be innocent, not naive."

This controlling impulse, which seems to be shared by most Christian home educators, has good and bad aspects. At best, it encourages parents to become deeply involved in their children's education, with beneficial results. At worst, it leads to children becoming intellectually and socially isolated in a world of their parents' making.

This is what happened to the writer Edmund Gosse, whose Father and Son (originally published in 1907) eloquently describes a kind of upbringing that was much more common before the 20th century. Gosse was educated by his father, a Nonconformist scientist who struggled in vain to disprove Darwin's theories. Having almost no contact with anybody outside a small circle of believers, Gosse could only challenge his father's teachings through experimentation. At one point, he prayed to a chair; when he wasn't struck dead for idolatry, he realised that his father might not have all the answers.

Christian home educators often say that they are trying to revive traditional models of education. And so they are. But what they are doing is radical, even revolutionary. By taking charge of their children's schooling, they are challenging one of the chief prerogatives of the modern state. As Graham Field says: "We should be the ones to decide our children's education, not the state. We are answerable to an authority higher even than the education authority."

Christian teaching methods

Many Christian home educators muddle through with a mix of secular and religious textbooks until GCSEs, when they hope to send their children to sixth form college. But for those who want a more structured educational experience, there is The European Academy for Christian Homeschooling (TEACH).

For a price, TEACH provides evangelical parents with training, support, and materials to educate their children up to 18. It expects that parents will run a highly disciplined school – something that many Christian home educators deliberately avoid. Children who need help with a problem are discouraged from calling out or sticking their hands in the air, for example. TEACH suggests they use flags to attract their parents' attention instead.

The science curriculum followed by TEACH pupils is, to quote the organisation's handbook, "completely Creation-based (taking a literal view of Genesis 1) and treats evolution as the theory it was intended to be." The literature syllabus includes Ben Hur and forgotten works such as Foxe's Book of Martyrs – a long, gory account of Mary Tudor's persecution of Protestants in the mid-16th century.

Much of the curriculum was developed in America. But Arthur Roderick, the director of Christian Education Europe (the parent organisation) dismisses the suggestion that the 500-odd British families using TEACH are the outriders of US Christian fundamentalists. "There's a fear that American right-wing religious fanatics are going to infiltrate our culture here," he says. "But that doesn't give due recognition to what is spontaneous and British about this movement."