Turbo C was a great C compiler. Embarcadero still gives away two (!) free versions of its C/C++ compilers today: the command line tools, and the entire IDE and toolchain in its Community edition.

https://www.embarcadero.com/products/cbuilder/starter

Depends on what sort of stuff they learned - remember that those students knew nothing about C so they'd be learning very simple stuff.

As an example, the free version of Turbo C++ 1.01 that is available through the Borland/Embarcadero museum (or was at some point, i don't know if still is) has ~34 introduction examples (referenced via their guide) that outside of a couple, use only basic stdio and stdlib stuff (these 2-3 examples that use a non-standard header use conio.h which AFAIK is borland specific, though Watcom/OpenWatcom and Visual C++ also seem to provide the used functions) without any DOS-specific functionality (be it far pointers or whatever) and could compile with any modern compiler.

What are you talking about? Delphi let's you build Android apps, not just DOS apps. And iOS, and Win64, etc...

I was referring to Borland turbo c/c++.

Got it, makes sense

Delphi never allowed to build DOS apps.