## Math Game: Six Hundred

Today I’m working on the next book in my Math You Can Play series, culling the games that don’t fit. Six Hundred is a fine game, but I can’t figure out how it landed in the prealgebra manuscript…

Math Concepts: addition, multiplication, parity (odd or even).
Players: any number.
Equipment: six regular 6-sided dice (my math club kids love this set), free printable score sheet, pen or pencil.

### Set-Up

A full game consists of eighteen rounds of play. Players may share the dice and score sheet, taking turns around the table. But for a large group you may want to have extras, so that two or more people can be rolling their dice at the same time.

### How to Play

On your turn, roll all six dice up to three times. After each roll, you may set aside one or more dice to keep for scoring, if you wish. Once a die has been set aside, you may not change your mind and roll it again.

After the third roll, choose an unused category on your score sheet. Count the dice according to the rules for that section, and write down your score. If your dice do not fit anywhere, then you must take a zero in the category of your choice.

When all players have filled their score sheet and recorded any appropriate bonuses (or penalties), whoever has the highest score wins.

### Scoring

Dice are scored in eighteen categories, in four sections, as follows. The maximum possible score is 600 points.

##### Numbers

Record the sum of only the dice showing that number. For example, if you rolled 1, 1, 3, 4, 4, 4, you could score 2 in the Ones category. Or you could score 12 in the Fours category, or zero in the Fives.

Bonus: If the combined Numbers score is 80 or more, add 35 points to your total.

##### Rungs (1–4)

Score the total of all six dice. Like a ladder, the score in each rung must be greater than the one before it. Rung 1 gets the lowest number, and Rung 4 the highest.

You may fill in the rungs in any order. But if you write 18 in Rung 2, then the score in Rung 1 must be 17 or less, and the score in Rung 3 must be at least 19.

Penalty: If the Rung scores don’t fit the ascending value rule, this category is worth zero.

##### Clusters

Score the total of all six dice, if they fit the rules for that category.

• Four of a Kind: at least four dice show the same number.
• Five of a Kind: at least five dice show the same number.
• Odds: all six dice show odd numbers.
• Evens: all six dice show even numbers.
##### Patterns

Score the amount shown for each pattern.

• Series: 30 points you roll 1, 2, 3, 4, 5, 6.
• Pairs: 30 points if you roll three pairs of matching numbers. Four dice showing the same number may be counted as two pairs.
• Triplets: 30 points if you roll two sets of three dice with the same numbers, such as three 2s and three 5s.
• Sextet: 36 points when all six dice show the same number.
##### Game Bonus

If you score at least one point in all eighteen categories, or if the only zero you take is for the sextet, then award yourself an additional 36 points.

### History

Players around the world have played poker-style dice games for ages. I grew up with Yahtzee, but you may know the game by Yatzy, Yacht, Generala, or another name.

Reiner Knizia included this mathematical version in his book Dice Games Properly Explained. And I found it online at Michael Ayers’s Stick Insect blog.

John Golden posted a simpler “Mathzee” game played with five dice on his Math Hombre blog — and while you’re there, be sure to check out his amazing Math Games page.

CREDITS: Feature photo (top) by rekre89 via Flickr (CC BY 2.0).

## Getting Started with Playful Family Math

One of the most common questions I get from parents who want to help their children enjoy math is, “Where do we start?”

Math games meet children each at their own level. The child who sits at the head of the class can solidify skills. The child who lags behind grade level can build fluency and gain confidence.

And (as Peggy Kaye pointed out in her book Games for Math) both will learn something even more important — that hard mental effort can be fun.

Now I’ve put together a short, inexpensive book to help families begin playing with math.

Let’s Play Math Sampler: 10 Family-Favorite Games for Learning Math Through Play contains short excerpts from my most popular books, including a preview of two games from my work-in-progress Prealgebra & Geometry Games.

Don’t miss it: Order your copy today.

“Denise Gaskins is that sound voice of reason that comes into my head when I get agitated teaching. This isn’t performance — this is play. My kids aren’t on trial, they are learning to learn.”

—Sonya Post

“By exploring math in a playful way, your kids will be happy to learn and will discover an enjoyment of math in the process. You might even have fun, too! ”

—Olisia Yeend

## 2019 Mathematics Game: Playful Math for All Ages

Happy 2019! Have you set any goals for the year?

My goals are to continue playing with math (1) in my homeschool coop classes and (2) on this blog — and (3) hopefully to publish a couple of new books as well.

My favorite way to celebrate any new year is by playing the Year Game. It’s a prime opportunity for players of all ages to fulfill the two most popular New Year’s Resolutions: spending more time with family and friends, and getting more exercise.

So grab a partner, slip into your workout clothes, and pump up those mental muscles!

## Rules of the Game

Use the digits in the year 2019 to write mathematical expressions for the counting numbers 1 through 100. The goal is adjustable: Young children can start with looking for 1-10, middle grades with 1-25.

• You must use all four digits. You may not use any other numbers.
• Solutions that keep the year digits in 2-0-1-9 order are preferred, but not required.
• 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 create multi-digit numbers such as 10 or 201 or .01, but we prefer solutions that avoid them.

#### My Special Variations on the Rules

• You MAY use the overhead-bar (vinculum), dots, or brackets to mark a repeating decimal. But students and teachers beware: you can’t submit answers with repeating decimals to Math Forum.
• You may NOT use a double factorial, n!! = the product of all integers from 1 to n that have the same parity (odd or even) as n. The Math Forum allows them, but I feel much more creative when I can wrangle a solution without invoking them.

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.

## Holiday Math Puzzles and Activities for Christmas, Winter Break

Do you know of any great math-related seasonal games, crafts, or activities I missed? Please add them to the comments section below.

As you scroll through the links below, you find several puzzle graphics from the wonderful Visual Patterns website.

Use them as conversation-starters with your kids: What do you notice? How does each pattern grow?

For older students: Can you write a formula to describe how each pattern? What will it look at stage 43?

### A BIT OF FUN

Setting the mood: Enjoy this bit of seasonal fidgeting from Vi Hart. If you don’t understand some of the references, that’s normal! Pick a phrase, Google it, and enjoy the fun of learning something new.

Every year, some of my favorite websites offer a seasonal selection of activities to encourage your children’s (and your own!) mathematical creativity, one for each day in the run-up to Christmas.

### LET IT SNOW! LET IT SNOW! LET IT SNOW!

• Clarissa (@c0mplexnumber) demonstrates how to make beautiful, challenging origami snowflakes. She recommends beginners try the first few folds — which create a pretty cool design on their own. Let it Snow…

### PUZZLES UNDER THE TREE

• Unfortunately, the holidays come smack in the middle of flu season. Did you come down with The Grinch Bug?
• Speaking of Christmas carols, the Christmas Price Index shows the current cost for one set of each of the gifts given in the song “The Twelve Days of Christmas.” I wonder what’s the cumulative cost of all the gifts, when you count each repetition in the song?

### CHRISTMAS ADVENTURES WITH ALEXANDRIA JONES

Alexandria Jones and her family are fictional characters from my old Mathematical Adventures newsletter. Their stories appear sporadically as I find time to transcribe them from the back-issues. You can find them all on this blog page.

Here are all the Alexandria Jones stories Christmas stories, with activity and craft ideas…

Do you need to keep your kids busy and work in a bit of math practice? Try these Christmas word problems:

Or visit the sites below for worksheets to cover all ages:

CREDITS: “Circle Packing” feature graphic (top) by fdecomite via Flickr (CC BY 2.0). Picture pattern puzzles from Visual Patterns website.

Once again, some of my favorite websites offer a seasonal selection of activities to encourage your children’s (and your own!) mathematical creativity, one for each day in the run-up to Christmas.

Including an especially tough Advent meta-puzzle for truly determined problem-solvers…

Click the images below to visit the corresponding December Math Calendar pages.

### For Primary Students

Easier activities for elementary and middle school.

A problem or game that uses dice for each day in the run up to Christmas.

When you get to the Nrich website, click a number to go to that day’s math.

### For Secondary Students

Activities for middle and high school.

Most of the tasks require dotty paper or circles which you can find on the Nrich Printable Resources page.

When you get to the Nrich website, click a number to go to that day’s math.

“Because sometimes, in the midst of all the family fun, it’s good to put your headphones in and retreat into a word of your own, this year’s advent calendar brings you some of our favourite Plus podcasts. From the secrets of the Universe to the maths of football stadiums, there should be something there for everyone. Happy listening and happy Christmas from the Plus team!”

When you get to the +Plus Magazine website, you can tell which links are live because they jump to a larger size when you tap or mouse over the picture.

One link becomes live each day — so come back tomorrow and discover something new!

### Christmas Meta-Puzzle

Or try your hand at the biggest mathematical mystery of them all — and save Christmas!

“It’s nearly Christmas and something terrible has happened: one of Santa’s five helpers — Jo Ranger, Fred Metcalfe, Kip Urples, Meg Reeny, and Bob Luey — has stolen all the presents during the North Pole’s annual Sevenstival. You need to find the culprit before Christmas is ruined for everyone.”

If you solve all the clues and enter the answer on Christmas day, you may win a present for yourself, too.

### Still More Mathy Fun

Colleen Young has collected several more holiday math calendars — enough to keep your kids playing and learning well into the New Year. Take a look!

“Peanuts Christmas Panorama” photo [top] by Kevin Dooley via Flicker. (CCBY2.0)

## Playful Math Education Carnival 123: Hundred Chart Edition

Do you enjoy math? I hope so!

If not, browsing this post just may change your mind.

Welcome to the 123rd edition of the Playful Math Education Blog Carnival — a smorgasbord of delectable tidbits of mathy fun.

The Playful Math Carnival is like a free online magazine devoted to learning, teaching, and playing around with math from preschool to high school. This month’s edition features $\left ( 1 + 2 + 3 \right )^{2} = 36 \:$ articles from bloggers all across the internet.

You’re sure to find something that will delight both you and your child.

By tradition, we start the carnival with a puzzle in honor of our 123rd edition. But if you would like to jump straight to our featured blog posts, click here to see the Table of Contents.

Or more, depending on how you count. And on whether I keep finding things to squeeze in under the looming deadline. But if there are more, then there are certainly 36. Right?

## The 1-2-3 Puzzle

Write down any whole number. It can be a single-digit number, or as big as you like.

For example:
64,861,287,124,425,928

Now, count up the number of even digits (including zeros), the number of odd digits, and the total number of digits it contains. Write those numbers down in order, like this:
even 12, odd 5, total 17

Then, string those numbers together to make a new long number, like so:
12,517

Perform the same operation on this new number. Count the even digits, odd digits, and total length:
even 1, odd 4, total 5

And do it again:
145
even 1, odd 2, total 3

If you keep going, will your number always turn into 123?