<p>I teach a C++ course using Visual Studio.  One of my students has a Mac and was looking for an IDE to use on his machine. What would be good to recommend?</p>

Xcode
which is part of the MacOS Developer Tools is a great IDE. There's also
NetBeans
and
Eclipse
that can be configured to build and compile C++ projects.
Clion
from JetBrains, also is available now, and uses Cmake as project model.