Writing teachers from all disciplines and at all levels have been struggling with the issue of show not tell for centuries. I can't comment on how my colleagues encourage students to cast this demon out, but I can definitely remark on my own approach in introductory creative-writing courses. Basically, for the first half of the semester, I put my students through a drill in which they write "portraits" of people, places, and things. I tell them that what I'm looking for are physical details, and that I'm not interested in anything else. I don't care what their subject matter is, I don't want to see any clever summaries to put anything in perspective for the reader. I just want pure description in the realm of 150 words. Then, after they hand in their portraits, I come along with my red pen, circling words that "tell not show" like a tough-love tyrant.Read More
Prof Spitzer's observations apply as well to statistics. Too often, students are eager to "tell" the reader their conclusions, completely skipping the duty to "show" their reader how one reached a given conclusion statistically. For example, a learner may be tempted to conclude that a "strong correlation exists between x and y." This statement "tells" the reader that x and y are somehow related. However, the student is failing to "show" how x and y are related, as in a "strong correlation exists between x and y (r = .99; p < .01)" [note the statistically descriptive parenthetical extension to the sentence].
Good writing is good thinking, and while "telling" a story has its place, being able to "show" a reader the basis for one's reasoning is fundamental to good scholarship.
Source: Spitzer, M (2012, September 26), Teaching Students to Show, Not Tell, Chronicle of Higher Education.