A mini concert from Scotty McCreery at Burlington High School in Burlington, Wisc. ended in a rowdy Q&A session that included the 18-year-old singing 'Happy Birthday' to a student named Amanda. It's a birthday and a concert she won't soon forget.

The students were part of a contest to raise the most toys for Toys for Tots. Radio station FM 106.1 hosted the contest and selected BHS as one of five finalists for the grand prize: a visit from the 'American Idol' winner. Over 10,000 toys were collected total, with Burlington High collecting 2,700.

"They were good. They were a great crowd -- one of the better ones I've played in awhile," McCreery told Fox 6 in Milwaukee after the show. "I kinda was in their element, too, because I'm still in high school and I know where they're coming from being there."

In addition to being asked to sing 'Happy Birthday,' the singer fielded other questions like "How big is 'this big'?"

"Even bigger than you think," McCreery quipped to the shock of the audience (and, likely, the staff).

Watch Scotty McCreery Sing 'Happy Birthday' to a Fan