I agree, if I'm demonstrating a subject that I'm "passionate" about,
students are a bit more fired up. I then encourage them to find a subject
they find interesting or that seems to occupy a lot of their creative
thought processes and apply the techniques I have demonstrated.
I have been doing a lot of collagraphs with Asian art influences. This is
because I like this at home and I have many Japanese things in my house. I
will also do examples with the kids that I later frame and keep. They have
had bicycling themes as I have been into that sport for 25 years. I seem
to use what I'm into for my subject matter.