The Raspberry Pi is first and foremost a computer meant to get kids coding. Case in point, the Raspberry Pi Foundation's guide to making a cool little Halloween-themed spot the difference game that hides a goofy little prank.
The idea of the game itself is easy enough. You'll task the player with comparing two images to spot the differences between them. A timer runs in the background, then shocks them with a scary image and a spooky sound after a minute. It's a pretty solid little prank-game that teaches the basics of loading images and sounds in Python.
There's no actual mouse capture here, but you can add that in if you prefer. Either way, it's a perfect project for kids before the holiday.
Scary Spot the Difference [Raspberry Pi]