I keep a growing library of little one-page javascript apps for illustrating concepts and educating my two boys. Reviewing my commit history for the year, I was pleased to find I've added nearly 20 apps to it in 2017. I wouldn't have been able to build so many 20 years ago, but there's so much code available out there to copy-paste, programming often feels like playing with building blocks.

http://ideonexus.github.io/Explorable-Explanations/