This reward system can be used for different things. If your child does all their chores without being reminded, they move up a line...If they get a 100% on a test, they can move up a notch...for every book they read...etc.
You can do as many or as few gray lines as you want. Mine is set-up for 14 days.
When your child makes it to the moon they should be rewarded with something. My boys get a dollar when they reach the moon.