More mathematical insight from James Tanton…
2010 Mathematics Game Update

[Photo by pfala.]
Thanks to John Cook’s article about factorials in the recent Mathematics and Multimedia Carnival, we’re adding new rules to the 2010 Mathematics Game.
Let’s play with multifactorials!
10/10 is Powers of 10 Day
Alex Deals Out Equations
Looking around the room, Alex saw kids and parents moving from one table to another. Everyone seemed to be enjoying the Homeschool Math Carnival. She had six junior-high and high school students at her table, waiting while she shuffled her deck of cards.
“Okay,” she said. “These are Math Cards. I took out the face cards, so we just have numbers.”
Sept-Oct 2010 Math Calendars
As I was preparing for Wednesday’s Homeschool Math Club Games & Activities meeting, I remembered my old math calendars and thought, that would be a fun activity to offer. So I pulled up the files and discovered that the days of the week matched perfectly. What a cool coincidence!
So in case you missed the math calendars last year, or in case it’s been long enough that your children have forgotten, here are the “new” versions:
Addendum
Umm Ahmad created an easier version for young students:
Hobbit Math: Elementary Problem Solving 5th Grade
[Photo by OliBac. Visit OliBac’s photostream for more.]
The elementary grades 1-4 laid the foundations, the basics of arithmetic: addition, subtraction, multiplication, division, and fractions. In grade 5, students are expected to master most aspects of fraction math and begin working with the rest of the Math Monsters: decimals, ratios, and percents (all of which are specialized fractions).
Word problems grow ever more complex as well, and learning to explain (justify) multi-step solutions becomes a first step toward writing proofs.
This installment of my elementary problem solving series is based on the Singapore Primary Mathematics, Level 5A. For your reading pleasure, I have translated the problems into the world of J.R.R. Tolkien’s classic, The Hobbit.
UPDATE: Problems have been genericized to avoid copyright issues.
Continue reading Hobbit Math: Elementary Problem Solving 5th Grade
The Arithmetic Fairy

[Photo by trazomfreak.]
Homeschool Freebie of the Day (which introduced me to Number Stories of Long Ago) shares another gem today: an mp3 recording of The Arithmetic Fairy, by E. Nesbit, one of my family’s favorite authors.
Young Edwin is an English schoolboy who deplores his daily math class. He wishes he could easily solve the problems he faces each day…
You can download the entire book of fairy tales from LibriVox:
“The Arithmetic Fairy” is chapter 7. Enjoy!
The Cookie Factory Guide to Long Division
[Photo by scubadive67.]
Help! My son was doing fine in math until he started long division, but now he’s completely lost! I always got confused with all those steps myself. How can I explain it to him?
Long division. It’s one of the scariest of the Math Monsters, those tough topics of upper-elementary and middle school mathematics. Of all the topics that come up on homeschool math forums, perhaps only one (“How can I get my child to learn the math facts?”) causes parents more anxiety.
Most of the “helpful advice” I’ve seen focuses on mnemonics (“Dad/Mother/Sister/Brother” to remember the steps: Divide, Multiply, Subtract, Bring down) or drafting (turn your notebook paper sideways and use the lines to keep your columns straight).
I worry that parents are too focused on their child mastering the algorithm, learning to follow the procedure, rather than on truly understanding what is happening in long division.
An algorithm is simply a step-by-step recipe for doing a mathematical calculation. But WHY does the algorithm work? If our students could understand the reason for the steps, they wouldn’t have to work so hard on memory tricks.
Math Teachers at Play #24
[Photo by internets_dairy.]
Welcome to the Math Teachers At Play blog carnival — which is not just for math teachers! If you like to learn new things and play around with ideas, you are sure to find something of interest. Let’s start the mathematical fun with an arithmetic card game in honor of our 24th edition and a few number puzzles:
Game: Target Number (or 24)
[Photo by stevendepolo via Flickr (CC BY 2.0).]
Math concepts: addition, subtraction, multiplication, division, powers and roots, factorial, mental math, multi-step thinking
Number of players: any number
Equipment: deck of math cards, pencils and scratch paper, timer (optional)
Set Up
All players must agree on a Target Number for the game. Try to choose a number that has several factors, which means there will be a variety of ways to make it. Traditionally, I start my math club students with a target of 24.
Shuffle the deck, and deal four cards face down to each player. (For larger target numbers, such as 48 or 100, deal five or six cards to each player.) The players must leave the cards face down until everyone is ready. Set the remainder of the deck to one side.

