Then they learn to play the game. It’s designed to be intuitive. “If you have basic computer skills, then two hours of training is enough,” said Luis Miguel Artieda, program director of the Avina Foundation in Lima, Peru, which manages and helps to fund Minecraft redesign projects in Latin America. Mr. Westerberg and others said that even people who have never used a computer can build in Minecraft in three or four hours.

Avina’s biggest project is in the Villa El Salvador slum of Lima, an enormous park called Parque Mamá Lucinda, built on a space that spent decades as a garbage dump. It’s named for a resident, Lucinda Terrazas, now 80, who has been fighting for such a park for 40 years. “This was certainly her first experience with computers,” Mr. Artieda said. “She sat at a computer with two or three people, so she didn’t have to move the mouse herself.”

After the teams finish their designs, they present them one by one, and the group discusses priorities. This design process can last a weekend, or stretch out over multiple weeks — six Saturdays, for example.

In a Minecraft consultation, more people show up and give their idea than in a traditional community consultation. “There are power dynamics,” Nicolette Pingo, development facilitation manager of the Johannesburg Development Agency, said of traditional consultations. “Most of the time, it’s men speaking a lot,” she said. ”We don’t hear the voice of women.” Or of youth, or homeless people — who care intensely about the design of public space. “In Minecraft, even if you are shy you can put your point across.” Even if you don’t speak the dominant language.

Minecraft also helps people understand the project. An architectural drawing usually offers only a bird’s-eye view. But in Minecraft, players walk around a building, go inside, look out windows, climb a tree, run around a soccer pitch.

Some who work with Minecraft say it also encourages a richer discussion and more ideas. Many teenagers dream of playing video games for a living; James Delaney actually does it. Six years ago, when he was 17, he founded Blockworks, a company in London that conducts educational and marketing projects with Minecraft. (Here are some jaw-dropping examples; check out the three maps of London’s Great Fire of 1666).

In the undergraduate thesis he wrote last year, Mr. Delaney told the story of the Victoria and Albert Museum. When it opened a new entrance in 2017, the museum recruited Blockworks to run a Minecraft workshop asking children to reimagine the building’s dazzling white porcelain-tiled courtyard. None of the players had any verbal criticism of the courtyard. But most submitted redesigns that were very different; 75 percent of the players, for example, put in trees, water or plants.