Technically, it’s the MS-DOS version, not the Apple IIGS, but the emulator appears to work on a Mac so…
The real Oregon Trail from MECC is back! (Washington Post) (link to game page)
And so is Carmen Sandiego! (But neither work with sound and despite the FAQ I can’t find an “unmute” button.) I played Carmen on an MS-DOS machine, so that’s very familiar, although the mouse synchronization between computer and emulator is troublesome (works better in fullscreen).