Some 2,000 new summer schools running across England will attempt to put 65,000 poorer children on an "equal footing" with their wealthier peers, Nick Clegg said today.
The deputy prime minister said the "brain training" camps would help struggling primary pupils make a good start at secondary this September.
The schools are being funded by £50m targeted at disadvantaged pupils.
They will focus on literacy and numeracy, and art, music and sport.
There will also be sessions to help youngsters get to know their new teachers.
About £50m has been made available to schools through the "pupil premium" - extra funding for disadvantaged children - to run the camps this year.
Mr Clegg said: "This is £50m worth of extra brain training giving tens of thousands of disadvantaged pupils a flying start at secondary school.
"It's two weeks in the summer holidays where pupils can catch up on learning and get to grips with life in secondary school - in short, get in the starting blocks ready for the off in September.
"Those who struggle to make the transition are often among the poorest in society, but two weeks of activities can really help to bridge the gap.
Does anyone have these running in their area? Or perhaps you or someone you know has a child taking part?
I'd love to know how it goes and after the holidays how much improvement is shown.