Grace VanderWaal found a much less critical audience than Simon Cowell on “America’s Got Talent” when she performed for adoring fans at a concert fundraiser at Ramapo High School on Sunday afternoon.

The former winner of the nationwide talent show brought her ukulele to the stage and played for more than an hour to support Valley Hospital.

“It went amazing,” VanderWaal, 13, said after the show. “It was very high energy. The crowd was amazing and I enjoyed it so much.”

More than 600 people attended the show to raise money for the hospital's child and adolescent mental health initiative and Valley's "Butterflies" program. Butterflies provides a team that plans and assesses needs for families caring for seriously ill children at home.

“I love to see everyone knowing that they donated,” VanderWaal said. “That’s just a great thing to do.”

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VanderWaal was born at Valley but grew up in Suffern, New York. She approached the hospital about doing a fundraiser, according to Valley Vice President of Public Relations Diana Frankel.

“We were thrilled that somebody like Grace, who’s only now 13 years old, would consider doing something like this,” Frankel said. “She’s a busy girl … so for her to take time out of her busy schedule and do this for us is simply amazing.”

VanderWaal, aided by her signature ukulele, won season 11 of “America’s Got Talent” in 2016 at the age of 12. Judges for her season included Cowell, Heidi Klum Howie Mandel and Mel B.

Her debut EP, “Perfectly Imperfect,” came out in December 2016 and sold 150,000 copies along with more than 50 million streams online.

Life has been busy for the young musician since “America’s Got Talent,” she said.

“I’m working on my next album so I’ve been working really hard on that,” she said.

VanderWaal performed a variety of original songs and covers of popular tunes during Sunday’s concert. Some of her selections included “I Don’t Know My Name,” “Gossip Girl” and covers of “A Team” by Ed Sheeran and “The Climb” by Miley Cyrus. She swapped out her ukulele for a guitar during the two cover songs.

Fans filled the auditorium at Ramapo and lined up in the hallway to participate in the tricky tray raffle. Eight-year-old Maureen Hennelly, from VanderWaal’s hometown of Suffern, said she loved the show.

“I watched her every night on “America’s Got Talent,’” Maureen said. “She doesn’t care what other people say and she just made me think that you shouldn’t care what other people say. Just be yourself.”

Courtney Soloff brought her children after she received tickets to the concert from her sister.

“That’s why we came,” Soloff said, “To see the next Taylor Swift.”

Email: jongsma@northjersey.com