The expedition places were made possible thanks to a grant from Heart of Bucks, a community foundation that covers the whole of the county.
Action4Youth provides expeditions to schools and clubs at all three levels of the award, which is designed to help develop young people for life and work.
The youth charity has been awarded a grant of more than £20,000 over two years so fully subsidised places can be offered to a significant number of young people who would otherwise not be able to take part.
Jenifer Cameron, CEO of Action4Youth said: “Duke of Edinburgh is a world leading youth development and achievement award but the cost of the expedition programme can make it difficult for some young people.
"As a charity our aim is to give all young people the opportunity to challenge themselves, work with others and discover new skills and experiences that help them to grow in confidence and achieve success.
"By offering free expeditions to those who otherwise may not have been able to take part we can support even more young people and enable them to take full advantage of the benefits, fun and rewarding experience of the Duke of Edinburgh award.”
Peter Costello, CEO for Heart of Bucks said: “A particular donor of ours has always been a big advocate for the Duke of Edinburgh award and the positive impact it has on young people.
"It gives us great pleasure to be able to connect this donor with Action4Youth in order to fund places for young people who might otherwise miss out on a brilliant experience.”