The prince's award scheme was for everyone, he said

At a Buckingham Palace conference, he said the way in which youngsters had to learn about the world as they grow up was the same as when the scheme began.

The prince also dismissed claims the scheme was the preserve of the middle class as a "myth".

A two-day rock concert will be among events to mark next year's anniversary.

It will take place next July in Windsor Great Park.

'Just as ignorant'

"The point is young people are the same as they always were," he said. "They are just as ignorant.

"The conditions in which they are living has changed, but the principle of learning what goes on in the world is just the same.

Duke of Edinburgh Award scheme It was inspired by Prince Philip's Gordonstoun headmaster Dr Kurt Hahn In the 1930s, Dr Hahn began a scheme called the Moray Badge to challenge youngsters He later asked the Duke to set up a similar scheme for all young people in the UK Some 500,000 young people around the world are in the scheme at any one time

"They go to school to learn academic subjects. They [schools] vary in quality. This is just a bolt-on. It's extra curricula activities."

He said the scheme was available to a diverse range of people and that most boarding schools did not participate.

"The award does not specify who takes it up. It's open to everyone. It depends entirely on volunteers who round up people."

He said it was designed with day schools in mind, which did not have many extra-curricular activities.

Prince Philip was joined at the launch by his son the Earl of Wessex, a gold award holder and trustee of the scheme.

Award-holding celebrities were also there, including polar explorer David Hempleman-Adams, opera singer Katherine Jenkins and TV presenter Alice Beer.