- Review the terminology we have used in describing graphs. Such as relative maximums, minimums, asymptotes, non differentiable points, etc.
- Pair students and provide each pair with the 4 graphs. Ask which one doesn’t belong?
- After some time, ask students to just raise their hands on who said Graph A, B, C, or D. Do not ask for reasons.
- Ask each pair to come up with a reason for why each graph does not belong.
- Ask various pairs to describe why each graph does not belong.
- Provide each pair with chart papers and ask them to draw to 4 different graphs where someone could answer the question “Which one does not belong?”
- Ask students for criteria on making a WODB?
- Some ideas are that each would have an equal chance of being selected.
- There is something different about each graph.
- Uses aspects of graphing that we have taught.
- Trade sheets with other groups and have the pairs now create answers as to why each new graph does not belong with the other 3

Here the graphs right from Mary's site which would work well for a calculus class.

Here are some graphs for a Math 30-2 class.