This lectures' core is - Core-C019-W6S04-SelfSendsArePlanForReuse.pdf (or a variation) - CoreC019-W6S05-HookAndTemplate-V2.pdf - Core-C019-W7S07-AvoidIsNill-V2.pdf [ - Core-W8S02-Design-DoubleDispatch.pdf ] It is unclear that we will have the time to give the lectures on double dispatch. The two files - Extra-DoubleDispatch-StoneExercise-J.pdf - Extra-DoubleDispatch-StoneExercise.pdf (Pharo version) are kind of little challenge that can be done autonomously. The file Extra-DoubleDispatch-Dice.pdf is the lecture using the Dice DSL as context. The slides summarize the point but if you want to do the exercise: You can find the first part of the exercise in file - Exercise-DSL-V2.pdf (several videos are available at http://mooc.pharo.org probably in week3) - Exercise-DSL-DoubleDispatch.pdf