This is the 12th of 27 TV show episodes to teach kids (about 5th grade and up) programming using Scratch 2.
This episode:
1) introduces creating blocks with three examples, and
2) explores the Move Steps block with a planet orbiting the sun.
The first challenge shows several examples of creating blocks, including creating a block that draws a regular polygon. Then the new block is run to easily draw a triangle, a square, an octagon and many other polygons.
The last challenge works with a very simple approach to orbiting around a planet by using the "Move Steps" command block. The orbit is irregular - a bit braided - and ultimately not stable, but it's fun and leaves a fun program to play with!