Below are examples of games that, to one extent or another, are educational. Some were simply entertainment products created and sold by game development companies. Other games were developed by private developers, educational consortia, teams in higher education, and so on, for an explicitly educational purpose. All those below can be played in your web browser; you need not perform a download and installation process.
20th Century
Oregon Trail: https://archive.org/details/msdos_Oregon_Trail_The_1990
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Sim Ants: https://archive.org/details/msdos_SimAnt_-_The_Electronic_Ant_Colony_1991
Sub Battle Simulator: https://archive.org/details/msdos_Sub_Battle_Simulator_1987
21st Century
Pox and the City: Edinburgh: http://poxandthecity.blogspot.com/
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The Radix Endeavor: https://www.radixendeavor.org/
Darfur is Dying: http://www.gamesforchange.org/game/darfur-is-dying/
Places to find browser/based (no download) games
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Internet Archive's MS-DOS Games Library
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