The issue with Scheme is that it has very little relevance outside of academia. It's fine for making students learn that as an exercise to teach them that there are different ways of doing things and some of those ways can be wonderful. But you need to learn more than just that to become a proper computer scientist or software engineer.
Python is a useful language to know just because of how useful it is. But it's not a great language to teach functional or object oriented programming. I would actually use different languages for teaching those concepts. Back when I studied, those languages where Gofer and Smalltalk. Gofer is a Haskell dialect/predecessor. Haskell already existed but wasn't that common yet. Scheme was already old news in the early nineties.
I actually learned Java during the summer of 1995 as a second year student as a preparation to teach it to first year students. My university was progressive like that. I learned C in my first year. They switched to C++ the next year. By the fourth year I had been exposed to Prolog, Java, Delphi, C, C++, Gofer, Smalltalk, Modula, Pascal, Lisp (in various variants) and probably a few other things that I've since forgotten.
One of the wonderful courses we got taught us all about the UNIX command line (mostly HP UNIX at the time, and a little bit of Solaris). Things like pipes & filters, regexes, AWK, etc. Different courses would expose you to different tools and languages. I followed a few courses on expert systems and bayesian belief networks. That just required you to deal with the lisp dialects used for that. The people giving these courses were proper researchers too. And they just used what they would use themselves.
I did not fully appreciate it at the time, but Utrecht university had a wonderful computer science faculty with some amazing people. I learned functional programming from a young enthusiastic Erik Meijer who later joined Microsoft, Facebook etc. and built things like F#, LINQ and a few other things.