MARIAH CAREY, NE-YO and NICOLE RICHIE were among the stars who helped recognize young volunteers at NICK CANNON's fourth annual TeenNick HALO Awards on Saturday (17Nov12).

The rapper/actor launched the Nickelodeon bash in 2009 to honor teenagers who are making a difference in their communities by "helping and leading others".

Actresses Lucy Hale and Victoria Justice also turned up to hand out prizes, while Carey told reporters how proud she was of her husband for hosting and spearheading the event, which was taped at the Hollywood Palladium.

She gushed, "I'm super proud of my hubby, Mr. Nick Cannon. I think this is amazing, that he conceptualised the whole thing. Really, he's so involved in this. It's all about... giving back... That's what the awards are all about."

Tyra Banks, Justin Bieber, Josh Duhamel and Emma Stone each met one of this year's (12) four HALO Awards recipients to discuss their charity work, and footage of their visits will be shown when the special is broadcast in the U.S. on Monday (19Nov12).