CHARLOTTESVILLE, Va. (WVIR) - A Charlottesville High School teacher is back in the classroom after a major surgery that saved someone else's life.

Matt Shields is not your typical teacher. He spends, on average, 10 hours a day at the high school.

He loves helping his students, who say he serves as their role model.

But outside the classroom, he's also seen as a hero.

Shields loves lending a helpful hand, and he often spends his free time tutoring students or writing letters of recommendation for soon-to-be high school graduates.

The Charlottesville High School physics teacher keeps busy and makes it look effortless.

“There's kind of no limit,” Matt said. “I mean, there's 1,200 kids here and that’s 1,200 kids who I'm sure are passionate about something."

The former Wahoo created the engineering curriculum for CHS, and serves as an adviser for the after-school club called the Best All-Around Club of Nerds - better known as BACON.

“They're winning international competitions,” Bob Shields, Matt’s father, said. “He gets kids into MIT. It's just pretty amazing."

Shields' father is a proud parent. But he's also grateful for his son, especially after receiving an incredible gift.

"I went on a list a couple years ago - on the transplant list - but there are almost 100,000 people on the list," Bob said.

Bob Shields needed a new kidney.

“It turns out, Matt was a perfect match,” Bob said.

At first, Bob was reluctant to have his son undergo such a major surgery at his expense. However, after some convincing, they both went under.

“It's a gift that is just beyond anything I could have ever imagined,” Bob said.

“Arguably, it was kind of selfish because I love my dad and he's a great influence on my life and he's a great influence on my kids' life - my two kids, they’re ages 3 and 5 - they love their Poppy,” Matt said. “Keeping him around - that's free babysitting."

The father and son duo are now back on their feet, and Bob says he couldn't be more proud of his son.

“I know he has said that I was a role model, but I think we've switched places in the past few years,” Bob said.

Matt has just finished up his third day back at school on Friday, November 9.

He's pretty modest when it comes to all he's done, both for his students and his dad.

But father knows best – Bob says Matt is a pretty amazing teacher, father, husband, and, most importantly, son.