Statistics published yesterday show that the percentage of Year 6 boys who read during dinner-time, play-time, or in the evening has dropped from 29 per cent in 1997 to 17 per cent in 2002.
The plunge in interest in reading comes despite a dramatic increase in the proportion leaving primary schools able to read or write well since the mid-1990s - a success the Government says is linked to the introduction of the national literacy strategy in 1998.
However, boys lag behind girls in reading and ministers have set up a series of projects to tackle the problem.
The new statistics on boys' reading habits come from an annual survey of 10 to 15-year-olds by the Schools Health Education Unit in Exeter.
Dr David Regis, the unit's research manager, said a connection could be made between the drop in boy readers and the literacy strategy.
The strategy has come under renewed fire in recent weeks from authors including Philip Pullman, who say it has stopped children taking pleasure in books.
However, Dr Regis said that other data from the unit's survey of 37,150 young people showed that many leisure interests were competing for children's time and that reading remained popular with girls. Boys listed their favourite leisure activities as watching television, playing computer games, meeting with friends and playing sport.
The survey also suggested a lack of knowledge among pupils about sexually transmitted diseases. Nearly 45 per cent of 12 and 13-year-olds could not name a reliable form of contraception while 42 per cent of 10 and 11 year-old boys had not heard of HIV or Aids.
Other statistics showed that 40 per cent of 10 and 11-year-old girls said they were sometimes afraid to go to school because of bullying and 39 per cent of 14 and 15-year-boys said that they did no homework.
More than a quarter of 14 to 15-year-old boys said they believed that friends carried weapons for protection when they went out.
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