Darla Richards runs a K–5 school in Henderson, Nevada. She chose a math practice tool for the way it explains, and watched her school's math catch up with its reading.

Say a child subtracts 48 from 300, writes down 352, and moves on — a number bigger than the one they started with. "Students would accept an unreasonable answer — they didn't recognize when an answer couldn't possibly be right," says Darla Richards, principal of Estes McDoniel Elementary in Henderson, Nevada, a K–5 school in the Clark County School District. When she arrived, the school's reading data ran far ahead of its math data, in both proficiency and growth.

Richards first saw Happy Numbers while serving as an assistant principal shared between two schools, one of which had started using it. “I have a strong background in teaching math foundationally and having kids explain their answers,” she says. “When I watched students on Happy Numbers at that school, I was immediately sold on the way concepts were presented in the platform.”

In the school’s primary classrooms, students typically rotate through about four math centers: one with the teacher at the table, the others math activities, Happy Numbers among them. “With that format, every student uses it daily.”

Filling those centers is where teacher time goes. “They’re always looking for activities to fill them — sometimes just busy work — and preparing that takes a lot of time,” Richards says. “Happy Numbers is simply there, and it’s a high-quality activity for kids to engage in every single day.”

Resource teachers use it with small groups of students receiving special education services. “The kids work on Happy Numbers while the teacher watches, say, three students at once and asks them to explain their thinking. Their achievement has improved greatly.”

“When I came to Estes McDoniel, our ELA proficiency and growth percentages were far above our math data,” Richards says. “We implemented a few things, Happy Numbers being one of them, and now our math and ELA data — both proficiency and growth — are about equal. Our math has caught up, as it should.”

Of the changes she has seen in students, confidence stands out most. “I’ve definitely seen students become more comfortable sharing what they’re thinking, because they know it’s right. They know it makes sense to them.”

What surprised Richards was the depth. “I’ve seen the visual models it shows kids, which give them a real understanding,” she says. “That surprised me, simply because it has taken a long time for the field to shift toward that way of thinking.”

The fit with classroom instruction matters as much. “When students work individually in a program that’s personalized to their needs and matches the way you teach, that’s a win-win.”

Her advice to other principals: “It’s definitely worth it — worth every penny. Hands down, if kids use the program, their math skills will improve, and they’ll enjoy it while they work.” And on budgets: “In these days of tight budgets, be as creative as you can and find ways to fund it, because it’s definitely worth the money.”

Asked to describe Happy Numbers in a few words: “It’s a program that helps kids understand the why behind the math.”