Learning and Teaching Resources

Circles on a Torus
torus top

Torus A few weeks ago, a friend showed me this sliceform torus and asked, “How many circles can you draw on the surface of a torus that pass through a fixed point on the torus?”

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Against the Lone Genius
In Todos Cuentan I wrote some axioms that have been a useful foundation for my educational and outreach efforts. I also find them far from perfect, a constant work in progress, as any work of this sort must be. I'll post some slightly updated ones: Axiom 1. Mathematical potential is equally present in different groups, irrespective of geographic, demographic, and economic boundaries. Axiom 2. Everyone can have joyful, meaningful, and empowering mathematical experiences. Axiom 3. Mathematics is a powerful, malleable tool that can be shaped and used differently by various communities to serve their needs. Axiom 4. Every student deserves to be treated with dignity and respect. These statements should not sound revolutionary, but considering the current practices of the mathematical society, they are a pressing call to action.

The stereotypical image of a mathematician is that of an old man sitting alone in a room, surrounded by floor-to-ceiling bookshelves, papers strewn across the table, and perhaps a blackboard filled with equations. The reality could hardly be farther from this image. The bookshelves and chalkboards and papers all around bit is still true to an...

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Instructions for Making the Tangram

Tangram is a seven piece dissection puzzle. Here are instructions to make these from a piece of paper.