Dermatology residency programs feature a variety of didactic conferences. Many common teaching activities include book reviews, journal clubs, and grand rounds. One familiar activity featuring active learning is called “Kodachromes,” morphology conference, or simply unknowns: an attending physician shows dermatologic images to residents, and they describe what they observe, use the morphologic clues to provide differential diagnoses, and settle on a final diagnosis. Although most residents find unknowns stressful, the lessons learned will often remain in their memory for years, if not for their careers.