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Black Eyed Peas rapper Will.i.am, known for his sophisticated charm and clean-cut style, said he had "the thickest Mexican accent in the world" when he was a kid.

"See Moon Dog? Bit like Chicano man, you know," he told " Nightline."

William Adams - that's his real name - was born and raised in the projects of East Los Angeles. Every day, he said, his mother would send him off to get a better education at a charter school on the other side of the city.

"Ever since I was 7 I was shaking on the bus, going an hour away from home," Will.i.am said. "Coming back to a floor at night, right, we slept on the floor."

But the 37-year-old musician has come a long way since those days. Today, he is Will.i.am, a dynamo and true Renaissance man. His Black Eyed Peas hold the number 1 and number 3 slots on iTunes' list of most downloaded songs of all time. And he's been a producer for  everyone from Justin Bieber to Britney Spears, from U2 to Nicki Minaj.

As judge on the British Version of "The Voice," who steals the show with his enigmatic facial expressions, Will.i.am said some American fans think he's actually from England, where the Black Eyed Peas first tasted success.

But the rapper is also a philanthropist, an actor, a designer and a geek.

"Geek is the coolest thing in the world, the coolest folks in the world," he said.

Will.i.am is a robotics nut; he says he developed a passion after a chance meeting with inventor Dean Kamen of Segway fame.

"He asked me if I could help amplify his USFIRST [For Inspiration and Recognition of Science and Technology] program, which teaches kids 9 to 18 robotics," he said. "I was like, 'that's cool. I wish I was doing that when I was a little Will.'"

He recently attended the FIRST program's world championship in St. Louis and continues to be an advocate for having much more science taught in schools.