William, 32, congratulated performers after their show Tuesday at The Door, a center for at-risk youth in the city's West Village, and admitted, "It nearly had me in tears."
"That was incredible guys," he said. "It was amazing and should be on [London's theater district] the West End."
"William said he wanted to help me put this together," Steven Prescod, 22, a Brooklyn resident who told his personal story in the show, tells PEOPLE. "He gave me his contact number and said to reach out to him."
"They brought hope to me," Prescod continued. "I had a low period in my life and never in a million years did I expect I would be performing for the duke and duchess."
But William and Princess Kate inspired the youth performance group showcasing work done by the kink between The Door and CityKids Foundation.
"[Kate] made me feel that wherever you come from, you should not let that determine who you're going to be," said another performer, Daniella Augosto, 19. "We can be what we want to be. It makes you feel you are going in the right direction."
The performers said they found the royal couple surprisingly approachable.
"It was them asking the questions, instead of us asking about what life's like over there," said Jemiarah Kirby, 16.
Another who takes to the couple, Eduardo Gonzales, 22, was impressed by the pair's relationship.
"They are like peanut butter and jelly. They sync together, finish each others' sentences," he said.
William and Kate are dedicated to helping youths reach their full potential, particularly "through an arts education model that helps young people overcome difficulties such as family breakdown, poor mental health or low self esteem," their spokesman said.