SYDNEY, Nov 14 - Woo, the head mathematics teacher at Cherrybrook Technology High School in Sydney's northwest, started video tutorials five years ago for a student too sick to attend school.

His online Wootube videos have since garnered more than 80,000 subscribers and over six million views.

"Online lessons broaden my reach and my ability to teach way more than I physically ever could," Woo said on Tuesday, after being recognised for the 2018 NSW Local Hero Award.

"Places like Cobar and Broken Hill and Bourke, they write in and say they've watched the videos.

"In the middle of the night YouTube is still playing and I'm fast asleep."

But the online personality still believes when it comes to teaching, human engagement is key.

"My job is to inspire young people to hold them up to a higher standard and say you can do better than that," Mr Woo said.

"You're going to be a rocket scientist one day, you're going to be a nurse one day, your society needs your very best.

"No matter what technology there is available, education is a human activity."

Woo's parents moved to Australia from Malaysia in the 1970s so he and his siblings could receive a good education. 

It's for this reason the gifted student chose the teaching profession to give back or, as he says, "pay it forward".

"I could never pay my school or my parents back for the incredible sacrifices they made, but I do have the opportunity to help the next generation have the same opportunities that I did."