Scratch is a free online programming language that makes it easy to create games, interactive art, simulations, stories., music and more. There are large and active Scratch communities for teachers and students.
Scratch site with thousands of student-created examples.
ScratchED- MIT's Teacher community for Scratch
From Computer Science Concepts with Scratch (2013) by Michal Armoni and Moti Ben-Ari:
We suggest that you work on each task according to the following guidelines:
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