Youngster Grace Johnson will help police to slow down motorists after winning a competition to design a campaign sticker.
Grace, of Great Kimble School, was announced as the winner of a challenge to design rear window and bumper stickers.
The Slow Down Motorists campaign is being run by the Rural Neighbourhood Action Group (NAG) and the North West Chilterns Local Area Forum with support from local police.
Gillian Harrington, headteacher of Great Kimble School, said: “The children of Great Kimble School have benefited enormously from the supportive role offered by our local Neighbourhood Police team, both in visits to the school and joining our walking crocodile.
“As a Green Flag school, our pupils are very aware of the impact of cars on the local community, and are keen to be involved in keeping the roads safe.
“They enjoyed the project of designing car stickers, and were especially delighted when they learned that Grace had won the overall competition.”
Buckinghamshire County Councillor Paul Rogerson, who also chairs the NAG, said: “This event brings the message to all to slow down on our roads.
“Speeding traffic raises the risk of serious or fatal injury on our roads, impacts on the quality of life in our residential areas and is a danger to all.
“I would like to thank all the children who took part in this competition and congratulate those who are receiving awards today. All of them are helping to broadcast the slow down message to drivers on our roads.”