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Combination strategies

Jarrod Skeggs — Wed, 03 Jun 2009 12:00:32 +0000

This next round of posts will discuss the use of what we call combination strategies. By our definition, a combination strategy is using two or more multiplication strategies in conjunction with one another to solve a problem. Multiplying 3′s from Multiplying Time is a great example of a combination strategy. The strategy is to double first then add the number once again.

So, for example, 3 x 1 = 1 doubled, plus 1. Or, 3 x 2 = 2 doubled, plus 2. Again, utilization of this type of strategy will help students with multiplication of numbers far beyond the 12 x 12 multiplication table. Let’s put that to the test…

3 x 19 = 19 doubled, plus 19. Do you know the answer? If you answered 57 give yourself a pat on the back. Let’s try another one. 3 x 31 = 31 doubled, plus 31. The first person to leave a comment and include the correct answer in their comment is eligible to buy up to 10 Multiplying Time! CD’s direct from Mathmagical for $5.99 each. Tax and shipping included.

The “Identity”

Jarrod Skeggs — Tue, 02 Jun 2009 12:01:41 +0000

Often overlooked when teaching multiplication strategies is ensuring that a student understands the simple things like the “Identity”. The number 1 is the “Multiplicative Identity” for integers, real numbers, and complex numbers. In multiplication, any number multiplied by the “Identity” is equal to itself. While this may seem a bit fancy, it’s important to lay the foundation for this understanding in preparation for learning algebraic and trigonometric strategies down the road.

A sample of Multiplying 1′s from Multilplying Time! is embedded above.

What is Multiplying Time! about?

Jarrod Skeggs — Mon, 18 May 2009 20:39:58 +0000

The idea behind Multiplying Time! is quite simple; help students learn multiplication strategies that can help them solve problems far beyond the typical “12 x 12″ operation. By learning and memorizing strategies, a student will possess a tool that is far greater than the standard multiplication algorithm. Here are some examples:

Track numbers 2, 3, and 4 from Multiplying Time! teach doubling strategies. Track number 2 addresses multiplying by 2. When multiplying anything by 2, the answer is as simple as doubling. As an example, 8 doubled, or 8 + 8, equals 16. The same strategy enables a student to solve 37 x 2, or 37 + 37, which equals 74. (This of course presumes that the student is proficient at addition). Track number 3 addresses multiplication by 4. When multiplying by 4, the answer is as simple as the double-double strategy. As an example, 8 x 4, is just like saying, 8 + 8 = 16 (double), then 16 doubled, or 16 + 16 = 32. Take that a step further for multiplying by 8 using a double-double-double strategy. Staying with the number 8, you’d say 8 doubled, or 8 + 8 = 16, then 16 doubled, or 16 + 16 = 32, then 32 doubled, or 32 + 32 = 64.

Hopefully this gives you an idea of how utilizing a strategy is better than memorizing an algorithm. Using the double-double-double strategy, what is 37 x 8?

Learn to multiply the fun way

Jarrod Skeggs — Sat, 25 Apr 2009 13:08:38 +0000

Everyone knows that math can sometimes be drab, boring, and quite a challenge. For most folks, the word fun is probably not one that is typically used in the same sentence as math. One of our goals at Math-magical is to change that mindset.

We’ve created Multiplying Time!, an innovative tool that can be used to help elementary school students learn solid strategies for solving multiplication problems. We sell Multiplying Time! on iTunes for the most part but we also stock a limited number of CD’s for the same price as iTunes, $9.99, plus $3 shipping and handling. If you would like to order the physical product, please email us at sales@math-magical.com.