## True Scale Multiplication Grid

An innovative true-to-scale multiplication table has been developed by a UK math teacher who blogs at on Twitter @TheChalkface.

The cool thing about the multiplication grid is that each value is represented by a size-true number of squares. So 1 x 5 is represented by 1 row of 5 boxes. And 5 x 1 is represented by one stacked pile of 5 boxes. Perfect squares are, well, square!

Here’s the Original Coke True Scale Multiplication Grid

Compare this design with

## Snickers

I really, really like this estimation problem.

The bag tells you the total number of ounces of candy.

That gives you some perspective.

(1) having them predict
(2) then after the answer video discussing why their prediction was accurate/inaccurate
(3) ask if their predictions could have been made more reasonably and not just a guess
(4) ask them to determine the weight of each candy bar (using the package info)
(5) predict the number of bars that make up a pound
(6) take a standard Snickers bar and ask them to determine precisely how many minis make up a standard Snickers

### How many Snickers are in the bag?

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## Edison Lee Does Percent!

One of my favorite cartoons is “The Brilliant Mind of Edison Lee” http://edisonleecomic.com/

In today’s newspaper, there’s a great Edison Lee cartoon, and it’s tapping into the fear generated by the new Executive and his administration. And I developed it into a problem for my 6th graders.

Here goes:

According to one source, if you were to dig and build a storm or bomb shelter in the basement of a 1 family home, it would cost between \$5,000 and \$6,000.
If you could use the 25% savings that Edison Lee found in the newspaper, what would be the range in prices of a storm or bomb shelter?
Show all work and explain your thinking clearly!

## The Student-to-Teacher Dictionary

Sometimes students say precisely what they meant. “I don’t understand the question” means they don’t understand the question. “This is too hard” means it’s really too hard.

But sometimes, it takes a little translating…

Half of my classroom conversations go like this.

Student: “I don’t get the question.”
Me: [longwinded, exhaustive explanation of what the question is asking]
Student: “Yeah, I knew that. But I don’t get the question.
Me: “Oh. This is one of those conversations.”

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## 30-60-90 Triangle Theorem

Motion graphics were created by Mac Square. How do you make sense of the 30°-60°-90° triangle theorem? What activities or resources have you used with your students to investigate the why?

Source: 30-60-90 Triangle Theorem