NRich is a provider of mathematics curricula and lesson plans covering everything from basic addition through advanced algebra and geometry. What drew me to their site was their collection of free mathematics posters. There is a poster for each month dating back to February 2005. The posters display a mathematics “trick” or challenge question. Teachers can download and print any of the posters in the collection. Each poster in the collection is linked to a problem page that contains notes for teachers using the posters.
Below is an image of the July 2010 poster.

Applications for Education
The posters from NRICH’s collection could make a nice addition to a mathematics teacher’s classroom. Use the posters that have challenge questions as a “bonus” assignment or simply display them to keep kids thinking about mathematics when their attention wavers from the lesson you’re trying to deliver.

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