At St. Francis high school in California, there is something to be said about math teacher Jim O'Conner. The 70 year-old Vietnam vet says he is not here to entertain.

Math teacher donates blood
"It drives me crazy when people say school should be fun," says O'Conner. "It's nice if it could be but you can't make school fun."

That's his attitude in the classroom. And the students thought that was all there was to him until this past November. In fact, they discovered they didn't know the half of him.

Senior Pat McGoldrick was in charge of a student blood drive and visited the children's hospital in Los Angeles for a meeting. Anytime he mentioned that he went to St. Francis, everyone would ask about Mr. O'Conner. Nurses and staff mentioned how wonderful he is, leaving Pat speechless.

When Pat walked into the blood donor center, he noticed a plaque with Jim O'Conner's name at the very top; the record holder for blood donated.

Jim Oconner helps babies
Then he learned something even more unbelievable. When Mr. O'Conner isn't torturing kids with Calculus, he's at the hospital cuddling sick babies. Three days a week for the past 20 years Jim has volunteered, stepping in when parents can't.

inspirational math teacher
The nurses describe Mr. O'Conner as invaluable.

Sometimes you think you know someone, but you have no idea.