I've made up a set of simple Traffic Light emulation projects to introduce Scratch to 9-11 year olds.
http://scratch.mit.edu/projects/SimpleScratch/18279
http://scratch.mit.edu/projects/SimpleScratch/18283
http://scratch.mit.edu/projects/SimpleScratch/18324
The children can start off using the painting tools to make their lights and then go on to assemble a very simple script to do the emulation.
The suceeding projects show how the initial idea can be expanded.
regards
Simon
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