Earning money was Jack’s initial motivation for the stand because he longed for a $400 Lego Star Wars Death Star set that his father insisted he pay for himself. But there was an important nonfinancial perk to the project, too: “It was really fun,” Jack said.

From the start, Steve Bonneau wanted the lemonade stand to be a learning experience for Jack. Mr. Bonneau is a former nuclear engineer who has been an entrepreneur for more than 20 years. His current company, Buybak, buys and resells used consumer goods.

“We wanted to make sure that Jack wasn’t getting out the Country Time Lemonade, using cups we already had in our kitchen and ice from the refrigerator,” Mr. Bonneau said. “And then at the end of the day, whatever was sold was his profits, without taking out any expenses or learning the other side of it.”

Early on, Mr. Bonneau taught his son business basics. Now that Jack is in fifth grade and studies seventh-grade math, the lessons are more advanced. Mr. Bonneau said he guided Jack through wholesale pricing, applying for a sales tax license and establishing business relationships.

“It’s a collaborative effort,” Mr. Bonneau said of Jack’s Stands, acknowledging that his son’s age and the complexity of the business means there are things Jack is not yet capable of doing. These range from carrying and assembling the 40-pound wooden lemonade stands to solving business challenges like finding organic, locally made lemonade or meeting the requirements of new farmers’ markets they work with.

In 2015, sales for the business were $25,000. This year, it plans to add several new stands in the Denver metro area, and one in Detroit; this expansion will be financed by a crowdfunding campaign.