__Venn Diagrams__

## Main Concepts

Sets

Venn diagrams

Venn diagrams with four sets

## Duration

Part 1: 20 minutes

Part 2: 30 minutes

## Summary of Activity

There are two parts to this activity. The first is in the form of a challenge. Students try to find a way to draw a Venn diagram with four sets. The difficulty lies in the fact that there should be 16 regions representing each of the possible intersections of sets.

The second part of the activity starts with students completing the personality test. It divides each person into Introvert/Extrovert, Observant/Intuitive, Thinking/Feeling and Judging/Prospecting, leading to a combination of four letters like INTJ for example defining their personality.

After they do that, students need to place all personality types in the correct regions for a Venn diagram. This part is different for each student as I insist that their own personality must be in the center of the diagram.

## Notes and Insights

The challenge of drawing a Venn diagram with four sets enables the teacher to address many misconceptions about intersecting regions. It may be slightly outside the actual purpose of the unit on sets but very valuable nonetheless. Students are typically missing regions, but even more often, the same intersection appears in two different places, giving the illusion that the 16 regions are represented when they aren’t.