[hsm3]

My son and I got a lot out of a similar iPad app called Tynker, which we both ended up liking better than Scratch, which he used at school. Tynker has a physics engine, which opens up all sort of great game possibilities (we made a cheapo Angry Birds). Also as referenced above, Tynker has a slightly richer language that gets rid of the need for some bad practices (e.g., functions can return values, you can declare local vars vs all-globals-all-the-time, etc). Having the tool work well on a tablet also travels really well, and is a simpler container than a browser window for a really young kid.