Refresh Your Course without (Too Much) Pain and Suffering

See if this sounds familiar.

You’re scheduled to teach a course you have taught before that desperately needs revision. The content and pedagogy go back for a decade or more and are both sadly obsolete, or the grades have been abysmal and the students are threatening to revolt, or someone (the department head, a faculty committee, or you) has decided to offer the course online, or maybe you’re just bored and dread the thought of teaching it again.