MONKTON, Vt. -
A young girl in Monkton has turned her fifth-grade science project into a life-changing hobby, but it's not her life she's changing. She's changing the lives of other children, one hand at a time.
From playing with her dog to her budding interest in lacrosse, Sierra Petrocelli isn't your average 11-year-old.
She's a fifth-grader at Monkton Central School. She's a quiet kid, but not surprisingly to the people who know her well, Sierra has found an extraordinary hobby.
"Of course I'm a very proud mom," said Lianne Petrocelli.
Sierra develops prosthetic hands made from a 3-D printer. The idea started when she wanted to use a 3-D printer for her fifth-grade science project.
"I never thought I was going to actually build a hand. I thought I was just going to show pictures," said Sierra.
The printer lays down thin layers of plastic into a design made on a computer.
Sierra connected with a company called E-Nable based out of Chicago. The company makes the computer models of these hands for children. They sent Sierra a tutorial.
"To work it, you bend your wrist and it pulls these strings back and they go all the way through the fingers," said Sierra.
Sierra's teacher was amazed when she heard about Sierra's ambitions for the project.
"I asked her to think about how 3-D printing can change the world, improve something, change someone's life," said Katie La Riviere-Gagner, Sierra's teacher.
More important than the A she received on her project is the way in which Sierra has decided to use her talent. She's making a new hand for an 8-year-old in California.
Reporter Alex Apple: How cool is that. You're making a hand for someone in California?
Sierra Petrocelli : It's really cool. I thought it was going to end after my science fair project.
Sierra also developed the first ever prosthetic hand without a thumb.
"This hand is for the girl and it has no thumb because she has a thumb and I think it will work better," said Sierra.
The hand that Sierra will create costs just $50. Compare that to a prosthetic bought from a hospital and thousands of dollars are saved.
"I think my favorite part is helping someone... they can do more now and not just have to use one of their hands to do everything," said Sierra.
Sierra and her family will travel to California later this year, and they hope to meet the girl receiving Sierra's hand.
Alex Apple: When you give someone a hand you're really changing their life. Do you ever think about it like that?
Sierra Petrocelli : Yeah, it's really cool. I never thought that a 3-D printer could change somebody's life.
This self-described shy kid took her school assignment and turned it into a gift for others.
"That was the coolest project I think I've ever done," said Sierra.
Sierra says she'll continue making hands. E-Nable now sells hand making kits for purchase.