Welcome to the Math Teachers At Play blog carnival — it’s not just for math teachers!If you like to learn new things and play around with ideas, you’re sure to find something intriguing here. Don’t try to read all 40(!) posts at once; take the time to enjoy browsing. Savor a few posts today, and then come back for another helping tomorrow or next week.

At my fortieth birthday party, I got a few of those gag presents meant to remind me how terribly old I was getting. Math Teachers at Play is less than 40 months old (it used to come out twice a month), but just imagine how many great math posts have been included over the months, in all 40 issues.

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Ha! 40? Old? Hardly. I always like to remind people that if we had, say, 12 digits instead of 10, we would be using a 12-based number system. This would mean that different absolute numbers would bear the strangely all-important ends-in-zero form, and therefore that different ages would be considered significant. In many ways, the 40s have been the best decade of my life. May you find it so too😉