Nick Clegg today hailed an initiative to send employees into state schools to talk about their careers as the launch of an "army for aspiration".
The Deputy Prime Minister said he hoped the Inspiring the Future scheme would allow schoolchildren to "open their minds" about the types of jobs they could pursue.
More than 100,000 voluntary speakers who can inspire youngsters are set to be signed up by the Education and Employers Taskforce.
The scheme is meant to give state school pupils access to the kind of careers advice and first-hand accounts that many private schools offer.
Research by the taskforce suggests 80% of independent schools regularly have external speakers to talk to pupils about career options.
Mr Clegg, who attended the prestigious Westminster School, said: "A lot of this is taken for granted for people, like myself, who were lucky enough to go to fee paying schools. What we are saying is that should be available to all schoolchildren whatever school they go to across the country."
Addressing pupils at the Bishop Challoner School in east London, Mr Clegg said had been inspired to take an interest in current affairs because his history teacher had "terrified" him into believing World War Three would "happen in weeks".
Actress Joanna Lumley, who appeared on stage with Mr Clegg, joked that she had wanted to be Prime Minister, but insisted the Lib Dem leader did "not need to worry".
Giving the children advice on achieving their dreams, she added: "Say yes, be on time, be gorgeous - as you all are - show willing, be savagely polite and go for it."
The scheme is strongly supported by the Deputy Prime Minister, who is driving efforts within the coalition Government to improve social mobility and ensure poorer youngsters are not hindered in life because of their background.
Other figures supporting the scheme include Apprentice star and entrepreneur Karren Brady, actress Joanna Lumley and the head chef of The Ivy restaurant, Gary Lee.
Mr Clegg added: "Too many young people get the message that the best jobs are not for them.
"Inspiring the Future will give state school students the chance to see, hear and make a connection with someone in a career or job they might not have thought about.
"Today we're calling on doctors, nurses, lawyers, builders, business people, civil servants, farmers, mechanics, engineers and other working people to give up just an hour of their time to talk to students in their local state school about how they got where they are today.
"The power of making connections that inspire young people is immeasurable and can be life-changing.
"Many successful people can point to a moment in their lives when they were inspired to become the people they are today. Now, it's their turn to help young people fulfil their potential."
Sir Roger Carr, president of employers' organisation the CBI, said: "There is nothing more compelling for young people thinking about their future careers than meeting and speaking to inspirational people who do the jobs they are considering. That is why the CBI is pleased to support Inspiring the Future.
"We desperately need to tackle the corrosive effects of high youth unemployment in the UK, so I would urge employers to sign up to this initiative and encourage their staff to get involved and provide valuable insights into their careers."
Brian Lightman, president of the Association of School and College Leaders which represents 17,000 school leaders, said: "The world of work offers a bewildering range of opportunities for young people.
"It is immensely important that they have the chance to gain insights early on about different jobs and careers, especially when they cover areas outside their immediate experience."