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What’s In My Brain: H vs Arrow

What’s In My Brain: H vs Arrow

Two columns. One is an example, one isn’t. Can you figure out the hidden rule before the big reveal?

Letters With Symmetry

Letters With Symmetry

Let’s group letters by their symmetry, then create symmetrical words, and then symmetrical sentences!

Crossing Every Bridge Exactly Once (aka Eulerian Paths)

Crossing Every Bridge Exactly Once (aka Eulerian Paths)

How can you cross each bridge in this city exactly once?

How Many Will There Be? Chip Off The Block

How Many Will There Be? Chip Off The Block

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

How Many Will There Be? Earthworm

How Many Will There Be? Earthworm

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

How Many Will There Be? Courtyard

How Many Will There Be? Courtyard

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

How Many Will There Be? Checkerboard

How Many Will There Be? Checkerboard

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

How Many Will There Be? Crosses

How Many Will There Be? Crosses

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

How Many Will There Be? Squares in Squares

How Many Will There Be? Squares in Squares

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

Find The Pattern: Multiply Fractions

Find The Pattern: Multiply Fractions

What if you set the stage for students to discover how to multiply fractions?

Olympics: Medals by Population

Olympics: Medals by Population

Do big countries always have the most medals? Which smaller countries rank surprisingly high in the Olympics?

How Many Will There Be? Pyramids

How Many Will There Be? Pyramids

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

How Many Will There Be? Sliced Circles

How Many Will There Be? Sliced Circles

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

How Many Will There Be? Xs and Os

How Many Will There Be? Xs and Os

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

How Many Will There Be? Desks

How Many Will There Be? Desks

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

How Many Will There Be? Stairs

How Many Will There Be? Stairs

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

How Many Will There Be? Flowers

How Many Will There Be? Flowers

These flowers sure are getting bigger faster! How large will they be in step 10? What about step 50?

How Many Will There Be? Triangles Within Triangles

How Many Will There Be? Triangles Within Triangles

A triangle splits and splits and splits again. How many will there be in step 20?

Math Curiosity: Klauber’s Triangle

Math Curiosity: Klauber’s Triangle

In 1932, a leading authority on rattlesnakes, Laurence Klauber, discovered a startling pattern within a triangle of primes.

Math Curiosity: Ulam Spiral

Math Curiosity: Ulam Spiral

What if we make a huge spiral of numbers and then highlight only the primes? Well, a bunch of weird patterns show up!

Math Curiosity: A Pattern Packed Triangle

Math Curiosity: A Pattern Packed Triangle

Pascal’s pattern-packed triangle is a potent puzzle for pupils to ponder.

What’s In My Brain: Trapezoids or Not?

What’s In My Brain: Trapezoids or Not?

Which are trapezoids and which are not?

Exponents – How Low Can They Go?

Exponents – How Low Can They Go?

Using exponent patterns, can students predict what the 0th power will be?

Math Curiosity: The Coloring Problem

Math Curiosity: The Coloring Problem

No video gets me more email from students! How few colors can you use to color in any map so that no two, neighboring regions are the same color?

The Angles of a Triangle

The Angles of a Triangle

Why tell a kid the rules of a triangle when they can discover them!?

Analyzing Movies’ Success

Analyzing Movies’ Success

So should we make another movie in this series?

Math Curiosity: Odds & Squares

Math Curiosity: Odds & Squares

Why does the sum of the first 5 odds also equal 5 squared?

Math Curiosity: Primes and Squares

Math Curiosity: Primes and Squares

Can any perfect square be written as the sum of two primes?

Math Curiosity: Legendre’s Conjecture

Math Curiosity: Legendre’s Conjecture

It seems like there’s always a prime number between two perfect squares… but is this always the case!?

Math Curiosity: Twin Primes

Math Curiosity: Twin Primes

What do you call two prime numbers who are very close together?

Percents and Credit Cards

Percents and Credit Cards

Let’s buy something expensive with a credit card and then make only the minumum payments!