## Leap Years and the Number 29

Astronomer Dr Meghan Gray explains how messed up our calendar is. The mis-match between the length of a day and the time it takes the earth to travel around the sun makes a leap year necessary. From Numberphile.

## Math Teachers at Play #47 via Math Hombre

Welcome to the 47th edition of the Math Teachers at Play Blog Carnival!
http://bit.ly/MTAP47

The Number Dictionary reveals two particularly interesting facts about 47.

• 47 is a prime and a Gaussian prime.
• 47 is the difference between two squares.

I don’t think I’ve appreciated 47 nearly enough before this carnival. But we should move on since there are a lot of neat entries this month…

Go read MTaP 47 at Math Hombre –>

## Quotable: Theory vs. Real Life

I had the most beautiful set of theories you ever knew when I started out as a schoolma’am, but every one of them has failed me at some pinch or another.

— Anne Shirley (fictional)
Anne of Avonlea by Lucy Maude Montgomery

## *Update*

It’s time to register for World Maths Day, which will take place on March 7, 2012. Last year, more than five million students from 218 countries combined to correctly answer 428,598,214 World Maths Day questions.

Would you like to help break the record this year? Don’t delay:

• Registrations close March 5!

• Play with students from schools all around the world. Individuals and homeschoolers are welcome, too.
• The competition is designed for ages 4-18 and all ability levels. Teachers, parents and media can also register and play.
• It’s simple to register and participate. Start practicing as soon as you register.
• And best of all, it’s absolutely free.

## Do You Teach Math to Young Children?

Sue VanHattum is trying to convince the publishers that this excellent book would reach a wider audience if they made it available at a lower price. What do you think?

As anyone who has taught or raised young children knows, mathematical education for little kids is a real mystery. What are they capable of? What should they learn ﬁrst? How hard should they work? Should they even “work” at all? Should we push them, or just let them be?

There are no correct answers to these questions, and Zvonkin deals with them in classic math-circle style: He doesn’t ask and then answer a question, but shows us a problem — be it mathematical or pedagogical — and describes to us what happened. His book is a narrative about what he did, what he tried, what worked, what failed, but most important, what the kids experienced.

This book is not a guidebook. It does not purport to show you how to create precocious high achievers. It is just one person’s story about things he tried with a half-dozen young children. On the other hand, if you are interested in running a math circle, or homeschooling children, you will ﬁnd this book to be an invaluable, inspiring resource. It’s not a “how to” manual as much as a “this happened” journal. … Just about every page contains a really clever teaching idea, a cool math problem, and an inspiring and funny story.

— Paul Zeitz
Introduction to Math from Three to Seven