Writing teachers often emphasize showing over telling. And I point out, as a general rule, that most compelling stories employ about 80 percent showing and 20 percent telling (or similar formulas: 90/10 or 75/25). My students at Hopkins, after all, are mostly scientists so can easily get their heads around Newtonian numbers.
To demonstrate, I wrote the following quote on the board for the showing/telling formula.
“I saw a werewolf drinking a pina colada at Trader Vics, and his hair was perfect.”–Warren Zevon, lyrics from Werewolf in London