When Minneapolis mom Stephanie Brodegard leaves the grocery store, people do a double take.

Brodegard doesn't load the groceries — and her three kids — into the family minivan. Instead, they're all loaded on her cargo bike.

When she hitches a trailer to the bike, she can carry even more. "I can haul up to five kids or my three kids and a bunch of groceries," she said.

The bikes — "long tails" with an extended frame behind the seat or "front-loaders" with a big, low-slung bin in front of the handlebars — are being used by local riders to haul the bulky, heavy, everyday stuff of life: bags of compost, kegs of beer, barbecue grills, coolers, lawn mowers, boxes of cat litter, Costco-sized bales of toilet paper, even other bikes.

Surprisingly, they're proving especially popular with families, who see them as two-wheeled minivans.

Rob DeHoff, owner of Varsity Bike and Transit in the Dinkytown area of Minneapolis, said the decision to buy a cargo bike is largely driven by moms. "It's women who say, 'I don't want to have to drive,' " he said.

Some families are using them to downsize from two cars to one. Others, such as the Brodegards, are relying on the two-wheeled haulers to replace the family car altogether. At least for a little while.

Brodegard, her husband, Bill, and their three kids — Grant, 6; Darcy, 4; and Lewis, 1 — are halfway through what they're calling "the bike year."

"We just like adventures and we like bikes," Stephanie Brodegard said. "We like the Earth, too."

So they asked themselves, "How can we have an adventure with bikes that doesn't cost a lot of money?" The answer was to let Bill's parents drive away with their only car, a 2013 Hyundai sedan with heated seats.

Since March, Bill has been commuting by bike about 20 miles a day round-trip to his job in Bloomington, where he's director of food safety at Schwan's.

Stephanie, a stay-at-home mom, is using one of their two cargo bikes for every trip she needs to make — to school, church and the YMCA, as well as the grocery store. Her long-tail Yuba bike has a platform behind the seat to carry passengers or cargo and an electric-assist motor to help get up hills or ease long trips.

Cargo bikes aren't new. They're been around for decades, used for deliveries and other commercial tasks.

Luke Breen, the owner of Perennial Cycle in Minneapolis, started carrying front-loading cargo bikes about 11 years ago. Back then, they were marketed as a two-wheeled version of a pickup truck.

"It was a flop," he said.

Then about six years ago, he started selling Yuba bikes, which can be accessorized to carry passengers as well as heavy loads.

"It was all about carrying kids, and that just changed everything," Breen said.

DeHoff said he now sells so many cargo bikes that "it's gotten to the point where it's not a weird thing anymore," he said.

Going 'car lite'

Of course, not everyone is going carless like the Brodegards. Many, however, are going "car lite" with the help of a cargo bike.

Stay-at-home dad Casey Andrus of Minneapolis and his wife sold one of their two cars and replaced it with a cargo bike made by a Dutch company, Babboe.

Their bike features a big, low-slung wooden cargo box mounted between the handlebars and the front wheel of the bike. The box, which Andrus has decorated with Grateful Dead decals, has a bench seat and shoulder straps for a passenger and is big enough to carry Andrus' 2½-year-old son, Bruce, as well as the family's two 50-pound English bulldogs. They also take along a Bluetooth speaker to play the Grateful Dead as they ride.

"Bruce and I are big Deadheads," Andrus said. "I just chauffeur him and the dogs around when they need to go someplace."

Chrissy Kannas of Minneapolis has transported her four kids, ages 1 to 7, about 1,000 miles around town over the course of the summer, using an electric-assist cargo bike.

"There's no stress to it. You use it like a car. Pile them on, and go to the pool," she said. "We've hardly used the minivan."

Parents who use cargo bikes say they are an improvement over Burley-style, pull-behind trailers.

"The trailers really weren't that much different from riding in a minivan," Breen said. "On the cargo bikes, kids are much more engaged in the experience."

Andrus agreed. "It's more time that he and I talk," he said of biking with his son.

But the bikes aren't cheap. Nonmotorized cargo bikes can cost $1,000 to $3,000. And electric-assist models, such as the Yuba Spicy Curry bike used by the Brodegards, cost about $4,000. Still, riders say they can save money over the long haul by avoiding the expense of gas, insurance and repairs for a car.

A 'bike year'

On the first week of school, Stephanie Brodegard loaded Darcy and Lewis on her lime-green Yuba Spicy Curry to pick up Grant at school.

When they arrived at Burroughs Community School in south Minneapolis, there was another mom with her own cargo bike.

Melissa Albert had come to pick up her 10-year-old daughter, Kate, from fourth grade. When she bought the bike six years ago, she couldn't find it in a local shop, so she ordered it online.

"I really wanted to get exercise, and I wanted a way not to ignore my kids when I get exercise," Albert said.

After picking up Grant, the Brodegards biked to the Southdale YMCA in Edina. While Darcy took a tumbling class and Grant went to basketball practice, Brodegard biked with Lewis to a Target and loaded three sacks of groceries in the trailer before taking everyone home.

The Brodegards have a blog, The Bike Year, which they call an "adventure blog about a family whose big adventures might consist of getting rained on a lot." Posts are titled "How do you go to the airport?" "What do you do when it rains? (Part II)" and "This was actually Steph's idea."

In their blog, they admitted that Grant was at first skeptical about giving up the family car — even though it meant that they could keep the trampoline in the driveway.

"He was asking about our car daily. He was saying, 'When are we going to get our car back?' " Stephanie said.

Bill said he and Stephanie have a plan for the car, "but Grant will not like it."

Bill added, "Later on, when they are older, our children will have loads and loads of character. They will thank us. Or burn us in effigy."

The Brodegards aren't sure how their experiment will work over the winter. Stephanie plans to dress the kids in snow gear when it gets colder. Two of them will fit in the trailer, which offers some protection from the elements.

"I guess the third one will have to be tougher," she said.

She's also working on building a shelter out of plastic tubing that can fit over the back of the bike.

But for now, a cargo bike is the way the family wants to travel.

"It feels like an outing every time we go out," Bill said.