Show HN: Opensource webapp that aims to teach beginners to code

I've been working on this prototype for a bit of a website that tries to get beginners interested in coding.

I learned to program on a TI calculator by making ascii games using TI-Basic's draw text function. With this webapp I tried to recreate that kind of simplistic exploratory programming that I enjoyed.

Also I wanted to maybe get kind of a demoscene feel where beginners would try to create cool stuff right away and then share them with the world.

The basic idea is that it lets users write javascript programs that interact with a matrix of grids. By setting the color of each grid you can make graphical apps kind of like screensavers. Then you can save your program and share it with other people and other people can 'remix' or modify your program.

It's at an early but playable state now so I would love to get some feedback from the community on the direction this is going. Also its open sourced on github so I would also love anyone with ideas for improvements to contribute.

The URL is http://grids.cavecode.com

Thanks!