# December Advent Math from Nrich

[Feature photo (above) by Austin Kirk via Flickr (CC BY 2.0).]

Click on the pictures below to explore a mathy Advent Calendar with a new game, activity, or challenge puzzle for each day during the run-up to Christmas. Enjoy!

### Advent Calendar 2014 – Secondary

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# Math Storytelling Day: The Hospital Floor

[Feature photo above by Christiaan Triebert via flickr (CC BY 2.0).]

Have you ever heard of Math Storytelling Day? On September 25, people around the world celebrate mathematics by telling stories together. The stories can be real — like my story below — or fictional like the tale of Wizard Mathys from Fantasia and his crystal ball communication system.

### My Math Story

My story begins with an unexpected adventure in pain. Appendicitis sidewhacked my life last week, but that’s not the story. It’s just the setting. During my recovery, I spent a lot of time in the smaller room of my hospital suite. I noticed this semi-random pattern in the floor tile, which made me wonder:

• Did they choose the pattern to keep their customers from getting bored while they were … occupied?
• Is the randomness real? Or can I find a line of symmetry or a set of tiles that repeat?
• If I take pictures from enough different angles, could I transfer the whole floor to graph paper for further study?
• And if the nurse finds me doing this, will she send me to a different ward of the hospital? Do hospitals have psychiatric wards, or is that only in the movies?
• What is the biggest chunk of squares I could “break out” from this pattern that would create the illusion of a regular, repeating tessellation?

I gave up on the graph paper idea (for now) and printed the pictures to play with. By my definition, “broken” pattern chunks need to be contiguous along the sides of the tiles, like pentominoes. Also, the edge of the chunk must be a clean break along the mortar lines. The piece can zigzag all over the place, but it isn’t allowed to come back and touch itself anywhere, even at a corner. No holes allowed.

I’m counting the plain squares as the unit and each of the smaller rectangles as a half square. So far, the biggest chunk of repeating tiles I’ve managed to break out is 283 squares.

### What Math Stories Will You Tell?

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# 2014 Mathematics Game

[Feature photo above by Artis Rams (CC BY 2.0) via flickr. Title background (right) by Dan Moyle (CC BY 2.0) via flickr]

Have you made a New Year’s resolution to spend more time with your family this year, and to get more exercise? Problem-solvers of all ages can pump up their (mental) muscles with the Annual Mathematics Year Game Extravaganza!

For many years mathematicians, scientists, engineers and others interested in mathematics have played “year games” via e-mail and in newsgroups. We don’t always know whether it is possible to write expressions for all the numbers from 1 to 100 using only the digits in the current year, but it is fun to try to see how many you can find.

## Rules of the Game

Use the digits in the year 2014 to write mathematical expressions for the counting numbers 1 through 100. The goal is adjustable by age: Young children can start with looking for 1-10, or 1-25.

• You must use all four digits. You may not use any other numbers.
• Solutions that keep the year digits in 2-0-1-4 order are preferred, but not required.
• You may use +, -, x, ÷, sqrt (square root), ^ (raise to a power), ! (factorial), and parentheses, brackets, or other grouping symbols.
• You may use a decimal point to create numbers such as .2, .02, etc., but you cannot write 0.02 because we only have one zero in this year’s number.
• You may use the overhead-bar (vinculum), dots, or brackets to mark a repeating decimal.
• You may create multi-digit numbers such as 10 or 201 or .01, but we prefer solutions that avoid them.
• You may use a double factorial, but we prefer solutions that avoid them. n!! = the product of all integers from 1 to n that have the same parity (odd or even) as n.

[Note to students and teachers: If you want to take part in the Math Forum Year Game, be warned that they do not allow repeating decimals.]

By Denise Gaskins Posted in Puzzles

# 2013 Advent Math from Nrich

Click the images below to visit the Advent calendars, and your children can play with math every day until Christmas! You may also enjoy:

“This Advent Calendar has a new activity for each day in the run-up to Christmas. All the activities are based on the theme of Planet Earth.”

“Behind each door of the Advent Calendar is one of our favourite activities with videos. Watch and enjoy!”

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# Every Day Is Math Day

Would you like to create your own math holiday? Look here for tips and sign-maker links:

Leave a link to your Happy Math Day post in the comments below, so we can all celebrate!

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# Happy Square of a Square Day

### In Response To

Make your own “Happy Math Day” sign:

Here’s a fun activity for any age that will encourage your children to play with numbers:

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# 2013 Mathematics Game

feature photo above by Alan Klim via flickr

New Year’s Day

Now is the accepted time to make your regular annual good resolutions. Next week you can begin paving hell with them as usual.

Yesterday, everybody smoked his last cigar, took his last drink, and swore his last oath. Today, we are a pious and exemplary community. Thirty days from now, we shall have cast our reformation to the winds and gone to cutting our ancient shortcomings considerably shorter than ever. We shall also reflect pleasantly upon how we did the same old thing last year about this time.

However, go in, community. New Year’s is a harmless annual institution, of no particular use to anybody save as a scapegoat for promiscuous drunks, and friendly calls, and humbug resolutions, and we wish you to enjoy it with a looseness suited to the greatness of the occasion.

For many homeschoolers, January is the time to assess our progress and make a few New Semester’s Resolutions. This year, we resolve to challenge ourselves to more math puzzles. Would you like to join us? Pump up your mental muscles with the 2013 Mathematics Game!

By Denise Gaskins Posted in Puzzles

# Vi Hart: Snowflakes, Starflakes, and Swirlflakes

Vi Hart is back with some wintery fun!

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It’s always a challenge to keep up with homeschooling during the holiday season, but here’s a wonderful way to weave mathematics into your daily schedule: The Nrich Advent Calendars offer a fun math game or activity for every day in December until Christmas Eve. Click the image to visit the calendar that fits your student’s level.

## Advent Calendar 2012 – Secondary

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# Olympic Logic

I love logic puzzles! Nrich Maths offers four fun Olympics Logic puzzles. And be sure to check out the rest of their Nrich Olympics Math as well.

Medals Count

Given the following clues, can you work out the number of gold, silver and bronze medals that France, Italy and Japan got in this international sports competition?

• Japan has 1 more gold medal, but 3 fewer silver medals, than Italy.
• France has the most bronze medals (18), but fewest gold medals (7).
• Each country has at least 6 medals of each type.
• Italy has 27 medals in total.
• Italy has 2 more bronze medals than gold medals.
• The three countries have 38 bronze medals in total.
• France has twice as many silver medals as Italy has gold medals.

Go to Nrich Maths and try all four puzzles!

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# Why Every Proof that .999… = 1 is Wrong

Vi Hart repents with an update to her last video: “Take that, mathematics!”

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# Happy Birthday, Einstein (Part 3)

In 1905, when he was 26 years old, Albert Einstein rocked the scientific world with a series of papers that changed our understanding of the nature of the universe. At MinutePhysics, the celebration continues:

## More Einstein Videos

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# Happy Birthday, Einstein!

March 14th is Pi Day, and it’s also Albert Einstein’s birthday. In honor of Einstein, MinutePhysics is posting a series of videos on his “wonder year” of 1905, when he published several papers that eventually earned him the Nobel Prize.

## More Einstein Videos

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# Leap Years and the Number 29

Astronomer Dr Meghan Gray explains how messed up our calendar is. The mis-match between the length of a day and the time it takes the earth to travel around the sun makes a leap year necessary. From Numberphile.

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# Super Bowl XLVI Math Worksheet and Football Comic

Lance Friedman of MathPlane.com has posted two bits of fun in honor of Super Bowl XLVI. (Click the images to go to Lance’s site.) And if you’re a homeschooler, Currclick is offering a Super Bowl Mini-Helper free this week.

# 2012 Mathematics Game

photo by Creativity103 via flickr

For our homeschool, January is the time to assess our progress and make a few New Semester’s Resolutions. This year, we resolve to challenge ourselves to more math puzzles. Would you like to join us? Pump up your mental muscles with the 2012 Mathematics Game!

## Rules of the Game

Use the digits in the year 2012 to write mathematical expressions for the counting numbers 1 through 100.

Bonus Rules
You may use the overhead-bar (vinculum), dots, or brackets to mark a repeating decimal.

You may use multifactorials:

• n!! = a double factorial = the product of all integers from 1 to n that have the same parity (odd or even) as n.
• n!!! = a triple factorial = the product of all integers from 1 to n that are equal to n mod 3

[Note to teachers: Math Forum modified their rules to allow double factorials, but as far as I know, they do not allow repeating decimals or triple factorials.]

By Denise Gaskins Posted in Puzzles

# Christmas Math from Vi Hart

You can find just the song here: http://vihart.com/music/gauss12days.mp3.

## Carnival Reminder

Send in your submission for the Math Teachers at Play blog carnival by Wednesday night. The blog carnival website has been a little funky (though several posts have come through), so your best option is to email Roman directly.

While you’re waiting for Friday’s carnival, check out the new Carnival of Mathematics.

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These advent calendars feature a new math puzzle or game for each day of December until Christmas. Many of the activities are designed to be done in a group, but they work fine for home school families who play with math together. Enjoy!

## For Secondary Students

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# More Halloween Math

by kennymatic via flickr

An Apollonian pumpkin patch and Sierpinski candy corn:

Great ideas for mathy porch decorations:

My favorite blood-thirsty online game from Murderous Maths:

And more:

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# Halloween: The Math of Zombies

A new video from SingingBanana:

# Tau Day Limerick

So if working in radians you hate
(How can $\frac {\pi}{4}$ be really $\frac {pie}{8}$?),
By just switching to τ
= 6.28318…

# Happy Tau Day

6/28 is τ Day.
Tau = τ = one turn around the circle = $\frac{C}{r}$ = 2π = 6.28318…
How do mathematicians celebrate τ Day?
Protest! Share anti-π propaganda.
And eat two pies…

# Be My (Math) Valentine

Just as I was looking for a creative Valentine’s craft for Kitten, this showed up in my inbox:

Xi at 360 provides step-by-step instructions, with photos:

And for more Valentine’s Day fun:

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# Days of Christmas with Vi Hart

If you haven’t subscribed to Vi Hart’s blog yet, what are you waiting for?

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# 10/10 is Powers of 10 Day

Sunday, October 10th is Powers of Ten Day!

# Math Storytelling Day

[Photo and story by Nick Johnson.]

Celebrate Math Storytelling Day by making up and sharing math stories. Everyone loves a story, so this is a great way to motivate your children to play around with math. What might a math story involve? Patterns, logic, history, puzzles, relationships, fictional characters, … and yes, even numbers.

What story will you tell?

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# Valentine’s Day: Say It with Music

If you have trouble seeing the video, it’s here on YouTube. For more information about the singers (and lyrics to this and other songs), check out the Klein Four webpage.

P.S.: You may also enjoy the Valentine’s Day Fail over at Abstruse Goose.

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