Interland by Google - A game to help kids be safe, confident explorers online
Typescript - TypeScript allows developers to compile a superset of JavaScript to plain JavaScript on any browser, host, or operating system.
Kidpreneurs - Entrepreneurship for kids 6-12 years old
LiveScript - LiveScript is a language which compiles down to JavaScript.
KidTech - The best tech for kids & parents curated by Collab Fund
Kaffeine JS - Kaffeine is a set of extensions to the Javascript syntax that attempt to make it nicer to use.