Rust bandwagon

For scientific programming, I absolutely second the idea of teaching Julia. It is a good, clean, well-designed language, it is generally way faster than Python even if you directly translate your Python code, and if you pay attention to their performance tips, it can be as fast as C. I would say Julia is easier than Python for scientific programming (in particular, vectors and matrices are built-in, no messing with numpy etc).

C++ is just too clumsy for scientific programming, in my opinion.