As I was merrily going along teaching linear pairs and vertical angles and corresponding angles and such, it came to my attention that various students were not "there" yet with internalizing the pictures and definitions, so I came up with this activity: I like the activities I've seen where sometimes the answer is "none" and sometimes there's more than one answer, and sometimes the answers are repeated in different questions. I've tried to incorporate that style into these problems. I think it worked pretty well. I'm also giving them a quiz on 6 types of angle pairs for the next grading period. I told them they have to identify each angle pair correctly, and spelled correctly, and no abbreviations, and no doctor handwriting, and in a timed manner. If they miss ANY, they get a 0%, and they have as many tries in the next 6 weeks to get it 100% correct. I likened it to recognizing the letters of the alphabet. It sure would be a shame if they couldn't and/or it took them a long time to process the information. I restated the fact that geometry (math) is like a foreign language, and they have to have fluency with all the words. In other funny news. A student whose grade is suffering and who came in for tutoring today and was actually grasping things said, "wow, I should really listen more in class because this makes so much sense."