Venn diagrams are helpful in understanding the idea of a set and using attributes to sort items. This basic plan is an introduction with an added bonus of an applet that can be used to demonstrate the activity. If a classroom of computers is available, the Venn diagram activity is simple enough for independent use. There is also a version for classrooms that do not have access to student computers. While it cites a 5th grade Common Core standard, the activity is better suited for younger grades.