Rebecca Johnson and Jeremiah Parry-Hill—Expertise is a double-edged sword. Teachers can forget how long it takes to become an expert. Learners often can’t see that they’re novices.(Kruger and Dunning 1999) Experts can’t remember what it’s like to be a novice. Novices don’t believe they need help. How can the skillful teacher navigate this pair of ill-fated misconceptions?