The Scratch software was launched in 2007. It is free, and is available in nearly 50 languages. The scratch home site has lots of programming examples, many written by young adults, (8 - 16 years) so perhaps the first impression is that Scratch capabilities are limited to that age range.
Installing Scratch for the Arduino
A short while ago I raised an article covering the installation of Scratch which is a great developer application for the young but there is another more interesting developers tool equally with the young in mind, it is called "Scratch 4 Arduino" or "S4A" for short.