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Factors and Codes (Episode 1)

Factors and Codes (Episode 1)

Let’s use factors to encode and decode words.

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?

Math Curiosity: Magic Triangles

Math Curiosity: Magic Triangles

Can you make each side of this triangle add up to 9 using the digits 1-6?

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.

Fizz Buzz: A Counting and Divisibility Game

Fizz Buzz: A Counting and Divisibility Game

Ready for a tricky counting and divisibility game?

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.

Parentheses: How big of a change can they make!?

Parentheses: How big of a change can they make!?

Two tiny parentheses. One expression. How big of a change can they make? Bigger than you think.

Exponents – How Low Can They Go?

Exponents – How Low Can They Go?

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

Calculators, Patterns, and Multiplying By Decimals

Calculators, Patterns, and Multiplying By Decimals

Before teaching students the procedure for multiplying with decimals, how much can they intuitively glean from a structured play session with calculators?

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?

Why Is Our Calendar So Weird!?

Why Is Our Calendar So Weird!?

Why are there 12 months? Why don’t weeks fit into months evenly? Why don’t weeks fit into the year evenly? What’s going on with the calendar!

Place Value (Beyond Base 10)

Place Value (Beyond Base 10)

Place value is something we cover in elementary school. It seems simple, but I’d wager that very few adults really understand the topic. I sure didn’t until I worked with non-base-10 number systems in college. Your students can get a taste of this mind-boggling experience by imagining what it would be like if we didn’t have the number 9. What would each digit represent then?

Math Curiosity: Odds & Squares

Math Curiosity: Odds & Squares

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

Doubling Dollars

Doubling Dollars

Say you have a dollar. Say you can double that dollar each day: $1, $2, $4, and so on. How long will it take to reach… one million dollars? Not as long as you might think!

Math Curiosity: Waring’s Conjecture

Math Curiosity: Waring’s Conjecture

So, can you write every odd (greater than 3) as the sum of three primes?

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: Finding Primes

Math Curiosity: Finding Primes

Prime numbers are unpredictable! How can we possibly find them all? An Ancient Greek mathematician found one way!

Math Curiosity: Twin Primes

Math Curiosity: Twin Primes

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

Math Curiosity: Palindromic Number Conjecture

Math Curiosity: Palindromic Number Conjecture

Using this one weird trick, it seems that you can turn any number into a palindrome!

Math Curiosity: Collatz Conjecture

Math Curiosity: Collatz Conjecture

The Collatz Conjecture: start with any number and get to 1 using just two rules. It seems to always work…