This is an old revision of the document!
Writing Traffic Light simulators is a excellent educational tool
Programmers can start off simply by just creating one traffic light
Once that has been achieved, programmers can go onto extra tasks such as turning it into a pedestrian crossing simulator and adding a red/green person (or walk/dont walk) light
Then a button can be added - then a wait light - and beeping sound etc
Further development can be added by simulating a person crossing a road and even have cars driving around responding to the signals
It is a classic low barrier for entry - high ceiling project