The National Literacy Strategy recommends that pupils must be able to recognise 150 words by the age of seven. But a study by Jonathan Solity and Janet Vousden, of Warwick university, suggests that much of this learning is a waste of time, because written English is dominated by a much smaller number of words. Knowing the 100 words, first used in the 1960s Ladybird books, opens up any book, including adult fiction and non-fiction.
The research suggests that "back-to-basics" approaches to phonics teaching, supported last week by a major government report, are not the best way forward for children.
The researchers analysed more than 900,000 words in a range of adult and children's books and two popular reading schemes used in primaries. They found that by learning the extra 50 most-used words, children gained an understanding of at best an extra 4 per cent of the texts.
This time, they said, would be much better devoted to getting the children to read real books, where they would come across new words in context, rather than the reading schemes recommended by many phonics specialists.
Advocates of phonics "first and fast" suggest that pupils should not be exposed to text until they know all of the words it contains.
Last week's report for ministers by Jim Rose, former director of inspections, has been criticised by teachers for suggesting that pupils be taught according to a particular type of phonics instruction.
News 6, Platform 21, Primary Forum 24