In previous years I have taught my third-year Graph Theory option as a standard 25-lecture course of the “definition-theorem-proof” variety. Last year I gave it in an entirely different format, without consequent change of syllabus. I divided the material into nine units each containing text, exercises and solutions to exercises, which were Xeroxed and distributed to the students at the rate of one unit a week. I gave only one lecture a week instead of the usual two or three. And for two periods each week the students were divided into groups of about half a dozen, who met on their own to discuss the current week’s unit.