For Jennifer Knowles and her three boys, it was a family enterprise: selling lemonade and giving all the proceeds to help children in poverty.
"We were just right over here at the park right across the street from our house," Knowles told CBS News' Barry Peterson. "I wanted to teach my kids two important lessons of entrepreneurship and charity, lifelong lessons that all children should learn about."
The kid business, however, came with a very grown-up lesson: that Denver requires three permits to sell food and beverages on public property, regardless of age. Their lemonade stand was in a city park, and police shut them down for lack of permits that other concessionaires had.
Knowles said police were "just doing their job."
"And I'm doing my job trying to get the laws changed so it's a better opportunity for everybody involved," she said.
Eric Escudero from Denver's Office of Excise and Licenses said the solution is simple: just move onto private property.
"In most cases, kids don't have to worry about setting up a lemonade stand if they do it in front of their house," Escudero said. "The last thing that the city of Denver wants to do is discourage the entrepreneurship of kids."
The fight over lemonade stands is not isolated to Denver. The Freedom Center of Missouri said there are dozens of cases across the U.S. where local authorities have restricted kid-run concession stands. Country Time Lemonade evenor fines if they're busted for selling lemonade. So far, they have had more than 400 registrations and reimbursed five permit fees and fines.
The non-profit Lemonade Day is also lobbying local health departments to change regulations.
Utah is the only state to pass a law prohibiting local authorities from requiring kid businesses to have permits or licenses.
Knowles has now persuaded the Denver City Council to work on a similar law. And she's started an advocacy group called "Lemonade Stand Mama."
"I'm trying to make lemonade stands legal across my community and ultimately across the country," Knowles said.