A friend passes you a note with the following strange image.

She’s recently been interested in **topology**, the study of structures
which can be morphed from one to another without cutting or tearing,
such as the donut and coffee cup shown above.
**Can you decode the number pairs by finding five groups of
topologically-equivalent letters?** Try writing each group in alphabetical
order on the corresponding rows of the grid…

Like in the example above, MaPP puzzles are **fun** challenges
which get students learning and using **advanced mathematics** and
**problem-solving skills**.

## More Puzzles

MaPP open-sources its game books for use by anyone under a Creative Commons license. PDFs of previous High School Challenge game books are available at the following links.