The LEGO Programmable Brick gives children the ability to create physical artifacts, such as vehicles and robots,
and program them with interesting behaviors. However, programming is difficult to learn, even for adults. Children
often lose interest in further exploration of programming through adult learning mechanisms. Environments that
support a gradual transition from manual control of the physical artifact to complete programming substantially
simplify the process of programming. The combination of LEGOsheets and the Programmable Brick is an
educational environment that provides a gentle, enticing introduction to programming and the design of mechanical
artifacts. This paper introduces LEGOsheets, a rule-based programming environment that allows children to
simulate and manipulate the LEGO Programmable Brick.