Track: This is a progressive challenge used in the introduction to Scratch.

It introduces sprites interacting with colours and other sprites, saying,
stopping script, movement, the coordinate system as use by Scratch
variables and costume changes. Starting by driving a car round a track
with the cursor keys it builds up to the final version where the car
drives itself round.

For such exercises I have several numbered memory sticks so the
students can save their work to it. It does depend on the students
remembering their number! The stick contains a folder with the
challenge title containing all the sprite costumes that are loaded and
not drawn in the ‘paint new sprite’ section. In this case the race track
and car are drawn. Also the code for each stage. I hand out a crib
sheet for each stage and after a while if the students have not got it
to work can load the completed section. They can then use this for
the next stage.