The kids voted for their favorite vegetables, school cafeteria staff more accustomed to warming up frozen dishes learned how to slice fresh fruit and restaurants changed their menus.
And the experiment worked. A program that pulled a whole town into helping its children eat better and exercise more helped stop the kids from gaining too much weight, U.S. researchers reported on Thursday.
The children of Somerville, Massachusetts gained, on average, just less than a pound (half a kg) less than children who did not take part in the program, the researchers at Tufts University's school of nutrition in Boston found.
And it got them to eat broccoli.
For young children still growing rapidly, this was a significant success, study leader Christina Economos said in a telephone interview.
"All children are gaining weight because they are growing," she said. "We want to prevent weight gain over and above what they need to for development."
They did, Economos and colleagues report in the journal Obesity. Children who were overweight lost weight, or stopped gaining, and those who were lean continued to grow at a healthy rate.
Economos hopes the seeds of life-long healthy habits have been planted in these children.
They compared 600-odd children of Somerville to two other communities where life went on as normal. Their experiment incorporated the school lunchrooms, teachers, after-care, parents and even the local newspaper.