Thanks for bringing up tenure. I am a full-time lecturer but not on a tenure track. At my age, I can't risk losing this job.
However, to some extent, every class can be a teach-in. For example, I teach game programming. So I ask my class what they would do about the industry being so unwelcoming. I teach digital media. So I tell my students about the infamous "Lena" picture, why it became pervasive, and that it still circulates.
philip_cardella