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!

Have Little Ones? Try Moebius Noodles!

Moebius Noodles Fundraiser Badge

Would you like to do math with your babies and toddlers — real math, not just counting and simple shapes — but don’t know how? For the last few years, Maria Droujkova has been teaching parents to do advanced, fun math with young children. I had the chance to lurk on a discussion group this summer and thoroughly enjoyed it. Now she is taking the next step — and you are invited to join in the fun!

The Moebius Noodles project includes:

  • Cool math concepts.
    Symmetry, fractals, coordinate planes, functions, transformations, topology, and more.
  • Math that grows with your child.
    Games and activities are adaptable to a wide range of ages, from babies to teens.
  • Math your child owns.
    Plenty of variations and suggestions to help kids bring math into their own worlds.
  • Active and open support group.
    A community of parents who share stories and photos, discuss examples, modify games, and ask and answer questions.
  • Math therapy for parents.
    For those who feared and disliked math in school, this project offers a second chance as you experience the math-rich world around you through playing with your child.

Maria is offering a variety of “Secret Rewards” (including free copies of the Moebius Noodles book) to those who chip in toward the project. Check out her Moebius Noodles blog post for more information.


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 3

Photo of Javier times 4, by Javier Ignacio Acuña Ditzel, 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. Talk through these patterns with your student. Work many, many, many oral math problems together. Discuss the different ways you can find each answer, and notice how the number patterns connect to each other.

So far, we have mastered the times-1 and times-10 families and the Commutative Property (that you can multiply numbers in any order).

Continue reading How to Conquer the Times Table, Part 3

Sign Up for the MathCounts Club Program

The MathCounts Club Program provides enrichment activities and puzzles for 6th-8th grade math clubs within schools — and homeschool groups may join, too! Participants receive a free Club in a Box Resource Kit, which includes the Club Resource Guide, two game boards to accompany one of the meeting plans, 12 MathCounts pencils, and a MathCounts tote bag for the coach. (Apparently they had good intentions, but they didn’t follow through. My box had no tote.)

A school (or homeschool group) may choose to participate in the Club Program, the competition or both programs. Since these programs can complement each other, any school that registers for the MathCounts competition automatically gets the Club in a Box Resource Kit, too.

For more information, check out these links:


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 2

Photo of Eeva times 6, by Eric Horst, via flickr.

The question is common on parenting forums:

My daughter is in 4th grade. She has been studying multiplication in school for nearly a year, but she still stumbles over the facts and counts on her fingers. How can I help her?

Many people resort to flashcards and worksheets in such situations, and computer games that flash the math facts are quite popular with parents. I recommend a different approach: Challenge your student to a joint experiment in mental math. Over the next two months, without flashcards or memory drill, how many math facts can the two of you learn together?

We will use the world’s oldest interactive game — conversation — to explore multiplication patterns while memorizing as little as possible.

Continue reading How to Conquer the Times Table, Part 2