This. I did this with a math teacher (pre-calc and trig) I had at a community college years later when I was taking calculus etc in college and killing it (after having a less than stellar math education before and during highschool) and I think it was a huge deal to him. He really put his all into teaching that class and a lot of people probably went on to 4 yr college and didn't think much of it but after having professors that hardly spoke a word to their students and spent a straight hour just writing on a chalkboard I totally appreciated an invested, engaged math teacher.