The award is given by 10 Downing Street for outstanding volunteers making a difference to the community.
Acknowledging the award Jim and Tessa said: “This award means so much to us because it recognises the contribution of volunteers.
“We simply wouldn’t be able to run the triathlons without an absolute army of amazing volunteers who help us at the triathlons themselves but throughout the year. We would like to thank them – nothing would be possible without them.”
Last year, more than 1,000 children took part in the triathlon event at Marlborough College, raising £100,000 for Restless Development and other charities.
In a letter to Jim and Tessa, Boris Johnson said: “I know you do this with no thought of praise or reward, but allow me to offer my own recognition of how your unique initiative has inspired over 9,000 young people to raise millions of pounds, through sport, for their peers around the world.”
Rosanne Palmer-White, UK director at Restless Development, said: “Jim and Tessa have grown the Schools Triathlon Series from an ambitious idea in 2015 into one of the UK’s largest sporting events for young people, with more than 9,000 children raising over £1 million for Restless Development and more than 60 other charities.
“Their success is the embodiment of the kind of transformative leadership that we aim to inspire globally and supports us to continue training thousands of young people to lead in solving problems in their communities around the world.”