Students join Minnesota Virtual Academy (MNVA) every month, and they bring very different histories. The public online school, a program of the Houston Public School District in Minnesota, enrolls children who have moved from school to school and children who have missed large stretches of a school year, sometimes for mental health reasons.

“We have kids who are coming in at kindergarten level in third grade,” says principal Katie Macrafic.

A third-grade teacher can always find a third-grade game, Macrafic says. A third grader working at kindergarten level is harder to serve. “How do we engage them at the same place where they’re at,” she asks, “and then help fill in their gaps?” Math builds on itself every year, and a student who leaves kindergarten without solid foundations can carry the gap into the grades that follow. With 30 or 40 students, Macrafic says, no teacher can target every missing skill.

Macrafic first came across Happy Numbers as a classroom teacher in another district. She and her colleagues saw it as a tool they could use, and the kids enjoyed it. The school didn’t buy it as a daily program, so her class used it at a math center. She remembered how easy it was to set up her class.
When she became an elementary principal, she asked her teachers whether anyone had tried it. Nobody had, so she proposed a pilot. Teachers signed on quickly, since the program needed little setup at the start of the year and no daily prep.

That mattered in a school where new students arrive every month. Adding them to a class takes very little time, Macrafic says. Happy Numbers also runs through the school’s single sign-on, so students skip the passwords and multistep logins that come with everything else online. Even kindergartners work in it on their own.

Every student above pre-K takes an adaptive placement test, and their practice starts wherever it places them, whether that is kindergarten skills or grade-level work. Often these are skills the student never mastered and may not get from a whole-class lesson. Teachers don’t prepare separate activities for each level.

The practice still asks a lot of students. Math is hard work, Macrafic says, especially for children with gaps.

“They know what to expect, and they know that when they log in, they’re going to be working at their level. And so that confidence goes up.”

Teachers can also show students their own progress and set goals with them. When 20 or 25 minutes of Happy Numbers is on the schedule, Macrafic says, each child gets the practice they individually need.

Happy Numbers checks each student at the beginning, middle, and end of the year. In a virtual school, getting a student through a benchmark test is, in Macrafic’s words, “kind of like pulling teeth.” In Happy Numbers, teachers tell students to finish the test and keep working. There’s no fight, and the school still gets the data. Macrafic sets those results beside the district benchmarks to see how they line up and where students have gaps.

Those checks also showed where the growth came from. In 2025–26, MNVA had no schoolwide requirement for weekly minutes, and classrooms used Happy Numbers in different ways. Some teachers built it into a fixed routine; Macrafic describes classes that practiced three to five days a week for about 20 minutes. Others used it as extra practice. For those classes, she says, “it’s good practice, but they’re not seeing the same growth that you would have if you were doing it consistently.”

In classrooms that used the program regularly, she saw large growth right away. Her standout was a kindergarten class that used it very consistently.

Heading into 2026–27, Macrafic says the usage and growth reports make the case to teachers on their own. The reports put each class’s practice time next to its growth, so the classes that grew most are easy to find. “All you have to do is put that time in the schedule,” she says.

Among K–3 students who used Happy Numbers regularly, the share meeting or exceeding grade-level expectations moved from 61% to 95% by the end of the year.

The same data went to the district. Money for supplemental tools is hard to come by, and Macrafic says a school needs data to justify one. When she shared the year’s results at an administrators’ meeting, her superintendent asked, “What more could we ask for?”

In May 2026, Macrafic asked her staff whether they wanted to keep using the program. It makes their job easier, she says, and it gives teachers individual data on each student that no worksheet can. Their answer was:

“Don’t take it away from us.”