BOSTON -- It's a lesson that goes far beyond the classroom. A Lynnfield teacher inspires her students to give back to a fellow classmate and their community.

NewsCenter 5's Heather Unruh reported that Matthew Mazzarella, of Lynnfield, Mass., is a fourth-grader with a smile that lights up a room.

"He's very thoughtful of others. He loves to fool around," said Matthew Zahar, a student at the Summer Street School.

"He always tells jokes to everybody," said Jack Sullivan, Mazzarella's best friend.

"Matthew is just this really quiet, cool guy who has been through so much and you wouldn't know it," said Michelle Robert, a fourth-grade teacher at the Summer Street School.

This easy-going, shy 10-year-old waged a war against cancer.

"You go to the hospital thinking you'll be home in a couple of hours, and find out your son has leukemia. It's devastating," said Mike Mazzarella, Matthew's father.

Diagnosed at 9 years old, he endured pain and suffering from chemotherapy and a bone marrow transplant. His sister was the donor.

"Just seeing what this family went through. They're terrific. They're amazing. He's a great kid," said Robert.

Robert took Mazzarella under her wing when he returned to school. She's also the one who wanted to honor his long journey.

"I thought well rather than give me presents, 'why don't we take whatever money would have been spent and we'll walk'?" she said.

On Sunday, Mazzarella's classmates, their parents and teachers will walk in his honor at NSTAR's Walk for Children's Hospital.

"What could be better than kids helping kids. I think it's an amazing idea that she came up with," said Mike Mazzarella.

"I wanted to help him support other children, and help other people who had the same things as him," said Sullivan.

"And I want to help out the community," said Zahar.

"I'm excited to walk with them the people in class," said Matthew Mazzarella.

It's an uplifting way to end a very, difficult journey.

"I think somewhere down the line, I think we're going to realize that Matthew has a purpose in life. And yes, he got cancer at 9 years old, but he beat it," said Rose Mazzarella, Matthew's mother.