Quotable: From Calc 3

“We have 4 equations and only 4 unknowns so that gives us a fighting chance of actually solving it.”

— My daughter’s Calculus III teacher

“Of course, he was doing an easy problem compared to the homework. 😛 ”

— My daughter, Niner


howtosolveproblemsWant to help your kids learn math? Claim your free 24-page problem-solving booklet, and sign up to hear about new books, revisions, and sales or other promotions.

How to Conquer the Times Table, Part 4

Photo of Miss Karen (and computer) times 3, by Karen, via flickr.

If you remember, we are in the middle of an experiment in mental math. We are using the world’s oldest interactive game — conversation — to explore multiplication patterns while memorizing as little as possible. So far, we have studied the times-1 and times-10 families and the Commutative Property (that you can multiply numbers in any order). Then we memorized the doubles and mastered the facts built on them.

Continue reading How to Conquer the Times Table, Part 4

Moebius Noodles Photo Game

Hooray! Moebius Noodles tipped the bucket. Thank you to everyone who chipped in!

Now the Fun Begins

The first Moebius Noodles game is a celebration of the Möbius strip. To play:

  1. Post a photo with a Möbius strip anywhere online.
  2. Notify Maria: droujkova@gmail.com. She’ll add your picture to her Moebius Noodles slide show, with a link to your site, blog or Twitter.

And for dinner tonight, try Möbius Marinara!


howtosolveproblemsWant to help your kids learn math? Claim your free 24-page problem-solving booklet, and sign up to hear about new books, revisions, and sales or other promotions.

How to Understand Fraction Division

photo by Scott Robinson via flickr

A comment on my post Fraction Division — A Poem deserves a longer answer than I was able to type in the comment reply box. Whitecorp wrote:

Incidentally, this reminds me of a scene from a Japanese anime, where a young girl gets her elder sister to explain why 1/2 divided by 1/4 equals 2. The elder girl replies without skipping a heartbeat: you simply invert the 1/4 to become 4/1 and hence 1/2 times 4 equals 2.

The young one isn’t convinced, and asks how on earth it is possible to divide something by a quarter — she reasons you can cut a pie into 4 pieces, but how do you cut a pie into one quarter pieces? The elder one was at a loss, and simply told her to “accept it” and move on.

How would you explain the above in a manner which makes sense?

Continue reading How to Understand Fraction Division

Support Moebius Noodles, Update

Would you love to introduce your preschoolers to the mind-stretching wonder of math? Check out Moebius Noodles, an open community of mathematical resources for parents and educators of young children.

Moebius Noodles activities and games use stuff you already have around the house to explore symmetry, fractals, functions, transformations, topology, and more, in a way that is accessible to babies and toddlers (and their parents!) and easily adapted to include older siblings.

Even a small donation will help this amazing project get off the ground — and Maria is offering a variety of “secret rewards” (like free books, or a secret-message game designed especially for your child) to those who chip in now.


howtosolveproblemsWant to help your kids learn math? Claim your free 24-page problem-solving booklet, and sign up to hear about new books, revisions, and sales or other promotions.

Math Teachers at Play #42 via Math Is Not A Four-Letter Word

by Patrick Hoesly via flickr

Bon Crowder has woven a nice variety of math links into a creative story for the September Math Teachers at Play carnival. Enjoy!

To mix things up a little, this month’s Math Teachers at Play Blog Carnival is a love story – between two people and then their new cute daughter. It’s a story of the coolest carnival of all – having kids.

The Story of Bernice and John, Mathematician Parents . . .

Go read the whole thing!

Free Learning Guide Booklets


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