Prince Charles was visibly moved as a young man said he would "probably be on the streets" without help from The Prince's Trust.
Aidan Sayers's journey from school exclusion and unemployment to getting a home, job and car was recognised in an awards ceremony at St James's Palace.
The Prince of Wales became emotional when Mr Sayers praised his college tutor, Claire McGarvey, telling her: "I've got as much love for you as my grandma."
While accepting the Educational Achiever Award, Mr Sayers said: "Without people like Claire around us I don't know where I'd be. I wouldn't have a house; I wouldn't have anywhere to go; I wouldn't have job; I wouldn't have anything.
"Without the Prince's Trust I wouldn't be standing here, obviously. I would probably be on the streets. Because of what the Prince's Trust has done, what all you lovely people have done, I'm stood here today and I can't say thank you enough."
Another of the winners, Cordell Jeffers, supported thousands of black and ethnic minority students through resilience training, motivational talks and entrepreneur workshops. He received the Young Change Maker Award.
Speaking about all the winners, Charles said their stories "have alternatively moved me, made me laugh and cry".
He added: "I've come to know how proud I am of all of them, and what they represent in terms of the incredible amount of effort and determination they put in to all of this and to win their awards."
He also noted how "marvellous (it is) to be together again in person after this delay of 18 months or so, this dreadful pandemic".
The event gave the prince the opportunity to recognise the winners in person after they were presented virtually earlier in the year.
Ambassadors and supporters of the Prince's Trust also attended, including actors Richard E Grant and Colin Salmon, Edward Enninful, editor-in-chief of British Vogue, comic Hugh Dennis, presenter Kate Garraway and host Fearne Cotton.