Recently, I've been seeing more information on the idea of which one does not belong, kind of like Sesame Street with their song only the modern one usually has multiple possibilities. It allows students to look at 4 possibilities and choose which one they think does not belong but the choices are such that there is not only one "right" answers. I require students to explain why they chose their answer. It helps develop their mathematical vocabulary. In fact, if you go to this website started by M^3 (making math meaningful) blog. It has several divided into Shapes, Numbers and Graphs. I never though about using graphs but that would work well for my upper level students especially if the graphs apply to the unit we are working on.
After we've done a couple weeks of "Which ones does not belong?" I plan to have my students create their on on the iPad and send them to me to use in class. I like the form the website uses and it is an easy form my students can use. I believe we could easily use zoodle comic, doodle buddy or similar app to create these. It will help the students with their higher order thinking skills especially if I ask them to include possible answers with justifications.