A lot of the comments here seem to fall into the line of "Why would anyone use this Dropbox ? - you can just use rsync".

There's a huge gap between a Raspberry Pi which gathers dust in the corner and having a product that parents can buy their kids for xmas which they can use to teach themselves the basics of programming.

Yes, parents could source the components individually, install linux, setup up scratch, download some tutorials for their kids, etc. But realistically only very tech savy parents are going to be capable of doing that and even fewer of them actually will.