The Youth Sport Trust is in the final stages of negotiating a deal with the confectionery firm that will let schools swap chocolate wrappers for sports equipment. The deal may see pupils being encouraged to wolf down brands such as Dairy Milk and Crunchie.
Cadbury Trebor Bassett describes the deal as "a major corporate partnership" with the trust, a charity that supports the 161 sports colleges. But campaigners have described it as "irresponsible". They point out that one in 10 children is now obese.
The trust already has deals with other brands, notably sports footwear company Nike. The potential benefits were shown this week when Nike announced that it was donating almost pound;1m of sports equipment to 4,500 schools following a fun run in London last September.
Cadbury and the YST will run a Get Active campaign to encourage young people to do sport. The campaign is likely to be supported by Paula Radcliffe, world marathon record holder, and Audley Harrison, Olympic gold-winning boxer.
As well as equipment for schools, the deal will give the trust cash for some of its programmes.
Sean Sweeney, head of Plymstock specialists sports college in Plymouth, said: "It would not sit comfortably with what we are here to do. There is a need to balance the need for extra income with the desire to promote healthy eating."
A World Health Organisation report to be published in April is expected to criticise the amount of fats and sugars in chocolate bars.
Patti Rundall of Baby Milk Action, a group pressing the WHO to back a ban on advertising to children, branded the trust irresponsible. "Those trying to get people fit would do well to steer clear of chocolate," she said.
The Food Standards Agency is examining the effect of promotional activities on the eating behaviour of children. A report, which could include limits on such activity, is due to be published later this year.