When I first taught Solid State Physics [following Ashcroft and Mermin] I would introduce holes as the absence of an electron. I then discuss the effective mass of "electrons" and holes near the bottom and top of bands, respectively. I would not introduce the concept of a quasi-particle until several weeks later when I discussed electron-electron interactions and Landau's Fermi liquid theory.
Now I do it differently.
I explain how holes are an example of a quasi-particle with a positive charge and an effective mass [which can be significantly larger or smaller than the free electron mass].
This is a nice "simple" example of emergence. When you put interacting particles ["non-interacting" electrons interacting with a nuclei in a periodic lattice] together new entities emerge which has properties that are qualitatively different from the constituent particles.
[Aside: it is interesting that the only "interactions" between the electrons themselves are those associated with Fermi statistics]
As an aside, I then try to get students to think about some of the philosophical questions asking them to vote on and discuss the following questions:
Do you believe electrons exist? Are they real? Why?
Do you believe holes exist? Are they real? Why?