Microsoft Encarta: MindMaze (1994)
Mindmaze...

Before Wikipedia, there was Microsoft Encarta, and hidden inside it was one of the best educational time-wasters of my childhood—MindMaze.
It was a simple trivia game wrapped in a medieval fantasy setting, where I wandered through a castle answering questions to progress. I remember getting stuck on some impossibly tough ones, but the urge to see more of the castle (and prove I was smart) kept me going.
It made learning fun in a way that few other programs did at the time. Even now, I can still picture that pixelated wizard guiding me through the halls of knowledge.