This 27 minute screencast recording & narration covers making a "Bat Chase" game in the Scratch programming environment.
Scratch is a free programming educational tool from MIT for kids and teens. It can be used in the browser or downloaded to your Windows, Mac, or Linux PC. https://scratch.mit.edu/
In this game, the player must run away from bats that are chasing them, while trying to get the bats to collide with each other. (This is a clone of a type of game called "dalecks".) The viewer can follow along as the narrator puts the program together one code block at a time from scratch.
You can play this game yourself at https://scratch.mit.edu/projects/11776449/#editor
This video and others can be found at the http://inventwithscratch.com website.
These videos are released under a Creative Commons license and are free to copy and share.