I do not like Scratch simply because it is only available for PCs and Macs.
However, the Scratch web site does offer a realistic view of what kids can
produce. Sure the artwork looks childish ... that's because this is the
work of children. Squeak can do most of that stuff, and a whole lot more.
One of the great things about the Scratch site is that it tends to promote the FOSS way of doing things. You can download other peoples work and build upon it. SO while it is not yet available for Linux, it does offer this way of working that is rather unique and compatible.
Scratch: http://scratch.mit.edu/
Gary Dunn
Open Slate Project
http://openslate.net/