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Earth Day Every Day Mural

A collage of Dov's Earth Day Murals and Seeds of Peace Murals with schoolchildren from Los Angeles to the music of Sagewing, Earth Day Every Day

Tour of a Recycling Plant

This is a video from a tour of Vista Fibers Recycling plant in Texas.

Ways to Memorize Pi

• Memorize 4 at time
• Repetition through a song
• Putting the digits of pi to sequential music notes
• Memorizing a poem with the number of letters matching the digits of pi memory chart

Check Out Our Pi Video Pages

Pi Video by Zap!

Other Pi Music Videos

Video Playing Pi on the Piano

Learn About the History of Pi

• The Story of Pi
• A History of Pi
• Pi Day Article - Plan Your Celebration

Play or Sing Pi

• Listen to Pi on the Recorder
Read more »

What Is a Leap Year?

A leap year (or intercalary year) is a year containing one or more extra days (or, in case of lunisolar calendars, an extra month) in order to keep the calendar year synchronized with the astronomical or seasonal year. For example, February would have 29 days in a leap year instead of the usual 28. Seasons and astronomical events do not repeat at an exact number of full days, so a calendar which had the same number of days in each year would over time drift with respect to the event it was supposed to track. By occasionally inserting (or intercalating) an additional day or month into the year, the drift can be corrected. A year which is not a leap year is called a common year. Source: Wikipedia

April 22nd is Earth Day!

Earth Day can be a wonderful opportunity to spend time observing nature and to gain an appreciation of the beauty of math in nature. Here are some ideas to get you started!

Free Gifts for the Special Moms in Your Life

Happy Mother's Day!

Please enjoy this free download of "Son of Mine" from Googol Power's album, Addition Celebration.

Mothers just love when their kids do math!

Here are some Mother's Day math activities to make any mom proud.

1. A dozen Mother's Day roses cost $15.60. How much is each rose?
2. Bake your mom a Mother's Day cake. Make the measuring a challenge: half the recipe and then triple it!
3. Call your grandma to tell her much you love her. If you talk for 20 minutes at 5 cents a minute, how much does the call cost?

Cost of Trip to Visit Grandma for Mother's Day

Did you know that I am part Irish? So, of course this is always a special day in our house. My mother (who would make us green eggs and ham on March 17th) is ⅞ Irish. Can you figure out how much Irish blood my daughter has?

Get the answer!

I am ⅞ * ½ Irish!
My daughter is ⅞ * ½ * ½ = 7/32
Try working out your own family tree with fractions!

Will you be my math-en-tine?

Love is like Pi, natural, irrational and very important!

— Lisa Hoffman

The time of year approaches when symmetrical Valentine hearts flourish, Fibonacci flowers are sold by the dozen, sweetheart candies are sorted, and you can count up all the ways you love your Valentine... and math!

Click on the pictures to see bigger versions!

Are you getting ready for the holidays? You can still fit in some family math into your busy schedule. There's something here for all ages!

Holiday Calorie Count

Are you eating more than normal? I know I eat more chocolate over the holidays!

Try tracking what you eat and your activities for the day, charting the calories consumed and burned. This requires both measuring and arithmetic.

Demonstrate your results on a bar graph. This is a great time to also discuss nutrition and health. Do candy canes count as a red vegetable?