Are there any learning video games that could teach my high school son?

My two cents asked:


My son will be going to the 10th grade. He will graduate from 9th grade in less than two weeks. He loves video games, but i'm wondering just like they have games for preschoolers on reading, if there is something out there that can teach while playing a short video game for high schoolers. Maybe he could even learn a few things ahead before he starts 10th grade.

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