When Barbara Havrot retired from teaching in Ottawa, she took her passion for math into the online world of YouTube, where she now uploads videos of herself teaching everything from trigonometry to calculus.

The newly-retired woman started her own channel in the fall. She's uploaded videos delving into the Grade 11 math curriculum, and has even posted tests and exercises to help students.

"When you're retired you have to plan your days, and I was missing being part of the math world and helping kids," she told CBC Radio's Ottawa Morning on Wednesday.

"Grade 11 [university-stream] math is probably the hardest course in the high school curriculum …​ because it's a big step up from Grade 10 and kids often have a really hard time with it."

After teaching for more than 20 years, Barbara Havrot continues to support students by delivering math lessons on her own Youtube channel. 0:59

'It makes me feel pretty happy'

Her makeshift studio at home is simple. She uses a smartphone attached to a tripod, bendable lights from Ikea and blank sheets of white paper.

Havrot's passion for math began when she was in Grade 10, when she had a "wonderful" math teacher, she said.

"I did really well in it. Once you like something, or you have success in it, then you tend to put more effort into it as well because you see those results."

Havrot teaches everything from calculus to trigonometry in her makeshift studio inside her home in Cantley, Que. (Hallie Cotnam/CBC )

Her YouTube channel has about 50 subscribers, and her videos have been viewed more than 2,000 times, she said. Usually there isn't much activity on Fridays and Saturdays, but things pick up dramatically on Sundays, she added.

When a student misses a class or has trouble keeping up, teachers usually don't have the time to go over the lesson, which are sometimes more than 40 minutes long.

So students come to her YouTube classroom to learn the stuff they missed or had trouble grasping, said Havrot, who had been a teacher for 23 years.

"This is a great way for them to come back and learn a lesson from a teacher who knows her stuff," she said.

"It makes me feel pretty happy."