At Foss Swim School, a family-run chain based in the Twin Cities, the teachers know how to charm their audience.

Upon meeting a hesitant toddler clinging to his parent's leg on the pool deck, an instructor requests a high five and then mock-reels into the water with a splash.

"You're so strong, you pushed me in!" he says.

The little boy cracks a smile. A few minutes later, he's been coaxed into the pool.

With 90-degree-plus water, cheery photos of swimming children on the walls, and an enclosed viewing area stocked with a TV, Wi-Fi and toys, Foss' facilities are a far cry from the concrete municipal pools or seaweed-laden lakes where many Minnesotans learned to swim.

By making lessons as fun and comfortable as possible for kids — and their parents — Foss has become one of the largest privately owned swim schools in the country, with seven locations in Minnesota alone. And the families that go to Foss have become devoted fans of the school.

Matty O'Reilly started his younger daughter at Foss when she was just 16 months old. When she turned 3, the family took a trip to Florida, where she was fearless, belly flopping into the pool without a life jacket, already capable in the water.

"Compared to my older daughter, who didn't start at Foss until she was 4, there was no way this would have happened," he said.

Parents who bring their kids to the school say they're driven by the desire to keep their kids safe in the Land of 10,000 Lakes, where knowing how to swim is not only a recreational skill, but a potentially lifesaving one.

"We boat a lot so it was important for me that they know how to swim well," said Lindsay Lappi, a Foss parent for the past eight years.

Yet Foss' pricey lessons, as well as its largely suburban locations, put it out of reach for many. Among its financially secure, mostly homogenous clientele, there are few people of color, immigrants and others from groups most at risk of drowning.

Teaching underserved populations to swim has been a major focus for municipal pools and nonprofit organizations, some of which have, in recent years, upgraded their facilities to include warmer, shallower pools and class sizes on par with Foss'.

But those who can afford Foss say the school's "learning by play" approach is worth the money. Amanda Keenan, a parent of three Foss students, said they tried community center and health club lessons, but her kids learned more quickly with Foss instruction. "You get what you pay for," she said.

Foss' origins

The school's namesake, Jon Foss, is a 53-year-old former All-American college swimmer who oversees the multimillion-dollar business, and is still happy to get his hands wet. In addition to training the school's instructors, he regularly fits a few laps into his workday. (He traveled to Budapest last year to compete in the World Masters Championships.)

His lifelong passion for swimming was spurred by a family tragedy. When his mother was a teenager, she took her two younger brothers to a lake near their farm and the youngest one drowned. As a result, she made sure her children learned to swim. By age 8, Foss had joined a team.

When he started coaching in the late 1980s, he realized his instruction had been inadequate.

"To swim at a world-class level there are very complicated techniques you have to know," he said. "I'd swum all these laps and didn't really know what I was doing."

He developed a curriculum that broke those techniques down into easy-to-follow steps. As he refined his instruction, his team started winning state championships and setting national records.

He decided to start his own swim school when he realized how many of his swimmers lacked fundamental skills. In 1993, he launched Foss Swim School in Eden Prairie with his wife, Susan, whom he had met when he was coaching.

Jon and Susan divided up the school duties: He took "wet" (curriculum and instruction), while she handled the "dry" (administration and marketing). For the first class, Foss taught a dozen kids in an apartment complex pool. Now, they typically teach 26,000 kids a week.

Learning by play

Foss' pools are busy from 8 a.m. to 8 p.m., seven days a week.

At the Chanhassen pool on a Tuesday morning in July, multiple lessons were taking place simultaneously. Three young boys in goggles huddle around their teacher, taking turns at putting their faces in the water. Nearby, a couple of older girls push themselves to the pool's edge to practice their kicks.

Parents and siblings line the benches along the pool, but there's also an adjacent air-conditioned observation room, where kids can watch movies or complete puzzles, while adults scroll through their phones.

The Fosses, who built their business while raising five children, designed their pools for the parents as well as the kids. Accordingly, there are private changing stalls for families and poolside showers with waist-high splash guards so parents can assist their kids without getting wet.

Small class size, typically three or four students per instructor, is among the school's biggest selling points.

"Group lessons feel like individual lessons," Keenan said.

Parent Karissa Sipek said she likes the way the Foss instructors frame concepts so kids understand them, with skill-building masquerading as play. Kids ride on large foam mats that become imaginary magic carpets. They talk about making "monkey cheeks" before they hold their breath underwater, or "painting the ceiling" to describe the backstroke. In the same way that inside jokes strengthen friendships, Foss' silly lingo creates the sense that it isn't just a lesson provider, but a club.

But the entry price is relatively steep. A group lesson at Foss costs $21 per class, roughly three times the price of lessons at a municipal pool or YMCA.

"For the benefit of knowing how to swim, I'll pay for it," Keenan said. "I've heard several parents say, 'It's expensive, but it works.' "

Issues of access

While the swim school gets glowing reviews online, a few complaints suggest that completing the school's robust, multilevel curriculum could cost as much as a year's college tuition.

"It takes a lot longer than people realize to learn how to swim well," Foss said. "It's an investment."

He said he's more focused on offering high-quality lessons than universal access. That's the mission of the YMCA of the Greater Twin Cities, the area's dominant swim lesson provider for the past 160 years.

Programs at the Y and municipal pools have long focused on reducing barriers to swim lessons, whether that means financial assistance, transportation to and from the pool or help bridging language or cultural gaps.

The city of St. Paul, for example, offers low-cost group instruction (about $8 a lesson) as well as fee assistance. The Y offers free swim lessons and water-safety instruction, with programs that send instructors to teach underserved groups at apartment-complex pools.

Even though there's no shortage of places to learn, most people don't swim well.

A 2014 Red Cross survey found that more than half of all Americans can't swim or demonstrate basic water safety skills. Typically, between 30 and 50 Minnesotans lose their lives to water each year. And blacks and Asians in Minnesota drown at a rate nearly 1½ times that of whites.

Despite the cost, demand is so strong that Foss is opening a new location in Plymouth and plans to expand to other states next year. Many municipal and community programs, including the YMCA and the city of St. Paul, say their enrollment remains strong, even with Foss' growth.

As they see it, the rising tide of swim schools helps all Minnesotans float. And the more who can safely navigate the water, the better.