[Nezteb]

I think p5.js [1] is difficult to beat when it comes to in-browser creative coding, games included.

Daniel Shiffman has a YouTube playlist of various videos about making games with p5.js [2].

There is also p5play [3], which was made specifically for educational game development.

[1] https://p5js.org

[2] https://www.youtube.com/watch?v=AaGK-fj-BAM&list=PLRqwX-V7Uu...

[3] https://p5play.org/index.html