What was once a steady but unspectacular trade in academic text books sold to schools and colleges has been transformed with the advent of titles such as At Home With Spelling and Number Puzzles - all in response to an upsurge in parental involvement in their children's education.
There was a time when the parent who sat down with their offspring in the evening and took on the role of teacher was very unusual. But according to Margaret Morrissey, of the National Confederation of Parent Teacher Associations, that is changing fast. "Over the last few years it's quite amazing how many more parents have started teaching children at home," she said.
Driving this educational revolution is the introduction by the last government of Standard Assessment Tests (Sats), designed to measure schools' performance. Tests are set at ages seven, 11 and 14, and parents increasingly see them as benchmarks against which to judge their children's progress.
"Parents are just much more clued up than they used to be," Margaret Morrissey said. "With the introduction of the national curriculum you knew exactly what your child was supposed to be learning when. It's the same with Sats." Parental anxiety plays a big part too. Nobody wants their child's school to be bottom of theleague table.
Publishers have been quick to spot a huge market. Books aimed at five- and six-year-olds are particularly big business. Children's book clubs and outlets such as the Early Learning Centre have created sales way beyond what might have been achieved by bookshops alone.
The Oxford University Press is one of the leading publishers in this field. It produces workbooks on spelling, handwriting, numbers, and other disciplines as well as Sats tests. Sales, which run to hundreds of thousands, have doubled in the last three years. "It's all come about because of government pressure on standards," Brenda Stone, an OUP publishing director, said.
But aren't publishers guilty of exploiting parental fears? "I don't think we could be accused of making parents anxious," Brenda Stone said. "We're just responding to a need."
Margaret McGowan, of the Advice Centre for Education charity, is concerned that home teaching of such young children may be excessive. "There is a lot more competition among children now. It's been made so much clearer where your child is supposed to be at any given stage. And that's a good thing. But these tests are very narrow. They can only measure what is measurable. There is so much more that goes on in schools that is also about education."Reuse content