Are you tired of doing ALL of the teaching while your middle school students are minimally engaged? Or have you been inspired after reading Building Thinking Classrooms and want to try some of the strategies with your students? If so, use these “thin slicing” task cards to help your students build understanding and “discover” how to solve systems using the substitution method ON THEIR OWN! Progression of Math Skills:This set of 12 task cards will guide your students from basic substitution o