What they did
The poster, u/monoloni, wanted screen time for his boys, aged 9 and 6, to teach them something. With no coding experience, he used Claude Code on Opus 5.5 to build an interactive 3D globe in the browser, on Three.js, which Claude suggested. The loop stayed simple: the kids ask for a feature, he describes it to Claude Code, and the three of them test the result together. Feedback from other parents after an earlier post also fed the wish list.
How it went
The game, called My Earth Toy, now has more than 830 landmarks modelled in 3D, more than 470 animals that walk, swim or fly with a collectible dex, more than 180 vehicles to ride, a day and night cycle, a trip to the Moon, a location guessing game, quizzes and a daily puzzle, in English, Korean, Japanese, Chinese and Indonesian. It is free with no ads. He says his son's geography improved within days and that teachers have started using it in classrooms. He calls it a work in progress with plenty of bugs.
Worth knowing
The kids acted as product owners and testers, which kept the scope driven by real use. The poster did not say how much it cost or how long it took. A commenter asked how he got realistic animals rather than cartoony ones, and the thread did not get an answer, so the 3D asset pipeline is unclear.