Co-founder and chief executive Dave Cameron says his team has also has created a complete virtual classroom for teachers and schools, with tutorials, tests, and student management tools. It's due to go live this week.
The platform will include anti-cheating tools - useful when your brats are scattered at home during a lockdown. But even in normal times, Cameron says there's a big need for remote learning for extra tuition, and for the 41 per cent of students who miss at least one day per fortnight to catch up.
Before the Covid-19 outbreak was announced, LearnCoach had some 105,000 students using its service, with around 8000 paid, Cameron says.
Last week, it added 7000, including a record 4000 on the day the lockdown was announced, and it introduced its free offer (which as things stand, runs through until May 1).
"That's ten times the usual level for this time of year," Cameron says. It's not usually until mid-year that students start to worry enough for sign-ups to surge.
On top of that, around 1000 teachers have pre-registered for the online classroom management platform being launched this week.
Like all good startups, LearnCoach had its genesis in solving a real-life problem.
As a maths teacher at Otago Boys' High School, Cameron calculated that each of the students in his various classes needed 15 minutes of one-on-one time per lesson - which would take 25 hours a day.
Since that didn't compute, he made a video of himself explaining a maths problem, then put it online.
In its first week, it clocked 30 views. In the second week, 70, then in the third 3000.
"It blew my mind," Cameron said.
In 2012, he founded LearnCoach, with his older brother Mark Cameron coming on as chief technology officer, and expanded to cover all subjects.
The older Cameron brought the how-to smarts (he has a post-grad engineering degree) plus some useful early-stage company experience from his time as a developer with Publons - the Wellington-based academic publishing startup sold to a Thomson-Reuters spinoff in a multi-million deal in 2017.
The company was well established by 2018, with David (then 30) picking up a Young New Zealander of the year gong for his efforts.
Along the way, Icehouse Ventures bought in, becoming the only major outside investor with its 25 per cent stake. The brothers now employ some 17, and its CEO says it's in the black. What's next? LearnCoach has been piloting video tutorials for NZ university courses. It's also eyeing expansion across the Tasman.
But for the next few weeks, the aim is to get the new online platform for NZ secondary school teachers up and running.
Cameron says all going well, it will free educators from the menial tasks around online learning, and let them concentrate on teaching.