Have students scan this trigger image in the app LAYAR to reveal a video asking them to compare the graphs of AND OR inequalities on the number line. The graph of the AND inequality is supposed to be the meat in the sandwich and the graph of the OR inequality is supposed to be the two slices of bread. I have had great success using this visualization strategy to teach this concept in my high school Algebra I class. Perhaps you could use this in your own learning environment.
