Digital Kodomo BASE Launches "AI Game Plaza" -- a place to play, and post, browser games kids built together with AI

NPO Digital Kodomo BASE (Ota City, Tokyo; President: Tomoyuki Urushidani; "the organization") launched AI Game Plaza (https://games.digitalkodomo.jp/) on September 9, 2026: a website where children publish and share browser games they built together with AI. Every game is a single HTML file that runs in a PC or smartphone browser with nothing to install. Children taking part in the organization's programs can post games they finished themselves with an AI assistant; staff review each submission before it goes live. Authors appear under nicknames only, there is no visitor comment feature, and visitors can send a "like" to games they enjoy. At launch the site carries six sample games that the staff built with AI (Reversi, Invaders, Whack-a-Mole, Breakout, Snake and Memory). Use is free. The site is in Japanese.

Background

With generative AI, even children who have only just started programming can describe the game they want in plain Japanese, run it, fix it, and end up with something genuinely playable. The organization held "Programming Experience: Let's Build an AI Game!" workshops in March and April 2026 (March 28 report, April 4 report). At its summer 2026 events, participants in the laptop giveaway sessions (July 30 and August 1) and the AI certification course (August 6) also built games with Claude Code, an AI coding tool (summer events report), and the organization now uses AI-assisted game building in its after-school lab.

Until now, a finished game simply stayed on its creator's computer; there was no place for other kids to play it or respond. Believing that the loop of "build, show, get a reaction, build again" is what keeps learning going, the organization opened this site as a publishing space designed around children's safety.

Site overview

Name	AI Game Plaza (AIゲーム広場)
URL	https://games.digitalkodomo.jp/
Audience	Mainly junior-high-school students; anyone can play
Cost	Free
What you can do	Play games / send a "like" / see rankings (likes and plays, all-time and this week, top 10) / participating children can post their own games
How a game is published	Send the game file with a submission code issued by a teacher or staff member -> staff review the content -> publish. Each game page has an optional "author's note" where the creator can describe how they asked the AI and what they worked on
Sample games	Reversi (vs. CPU or two players), Invaders, Whack-a-Mole, Breakout, Snake, Memory -- all built by staff with AI, with the prompts and design choices described in the author's notes

Features

1. One HTML file, playable anywhereEach game is a single HTML file with no extra software or app. It runs as-is in the browser of a school or home PC or a smartphone. Games are up to 5 MB.
2. Designed around children's safetyAuthors appear under nicknames only; no real names or contact details are shown. There is no visitor comment feature -- the only reaction is a "like". Staff review every game before it is published. Games run sandboxed on a separate dedicated domain, restricting game code from accessing portal data.
3. Sharing how it was built with AIEach game page has an "author's note" where the creator can write how they asked the AI, what they fixed themselves and what was hard. The staff have written these for the sample games too. Game code is open to read, so children can learn from and build on each other's work.
4. Run on the organization's servers; no real name or email required to postThe submission form accepts the game, title, nickname, description, author's note, thumbnail and submission code. It does not ask for a real name or email address. Cookies help prevent duplicate likes and play counts; access information, including IP addresses, is recorded to investigate misuse and resolve technical problems.
5. AI used under staff supervisionWhen children build games with AI, they use accounts held by the organization under staff supervision. The rules are simple: never enter personal information such as real names, and never reuse other people's characters or assets.

What comes next

The organization will grow the collection through its after-school lab and events, developing the site as a place where participants publish and keep improving their own games. A "remix" feature for building on another child's game, and sessions for sharing how to work with AI, are under consideration. Schools and community groups interested in using the site are welcome to get in touch.

* The site is part of the organization's free educational activities. Copyright in each game belongs to its author.

* Details are as of the launch date. See the site (https://games.digitalkodomo.jp/) for the latest information.