Alex’s & Leon’s Homeschool Puzzle

While checking out the book table after a homeschool group meeting, Maria Jones glanced up to see her children laughing with some kids she did not recognize. Driving home, she asked about the new family, but Alex and Leon had been too busy exchanging silly stories to even ask the strangers’ names.

“Well,” Leon said, “the boy told me he has twice as many sisters as brothers.”

No way!” said Alex. “The girl told me that she has the same number of brothers and sisters.”

How can that be?

Continue reading Alex’s & Leon’s Homeschool Puzzle

Leonhard’s Block Puzzles

Leon’s wooden block puzzle Leonhard Jones is Alexandria Jones’s younger brother. He enjoys woodworking, and he cut a wooden cube into 8 smaller blocks to make himself a puzzle.

Puzzle #1

Leon painted the 8 blocks with his two favorite colors: red and forest green. When he was finished, Leon could put the blocks together into a red cube, or he could switch them around to make a green cube.

How did Leon paint his blocks?

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Happy Pi Day II

[Feature photo above by pauladamsmith.]

Now there is an ancient Greek letter,
And I think no other is better.
It isn’t too tall,
It might look very small,
But its digits, they go on forever.

— Scott
Mrs. Mitchell’s Virtual School

Time to Celebrate

Are your students doing anything special for \pi Day? After two months with no significant break, we are going stir crazy. We need a day off — and what better way could we spend it than to play math all afternoon?

If you need ideas, here are some great \pi pages:

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Math Links for Fun and Charity

Numbers
Photo by James Cridland.

Aargh! My computer died again. So I borrowed my daughter’s laptop and ran off to the coffee shop to write blog articles — and discovered that all the outlets on the wall here are fake. Why would they do that? Anyway, before the laptop battery dies, I want to share a couple of math links with you…

Continue reading Math Links for Fun and Charity

Euclid’s Game on a Hundred Chart

Math concepts: subtraction within 100, number patterns, mental math
Number of players: 2 or 3
Equipment: printed hundred chart (also called a hundred board), and highlighter or translucent disks to mark numbers — or use this online hundred chart

Set Up

Place the hundred chart and highlighter where all players can reach them.

How to Play

  • Allow the youngest player choice of moving first or second; in future games, allow the loser of the last game to choose.
  • The first player chooses a number from 1 to 100 and marks that square on the hundred chart.
  • The second player chooses and marks any other number.
  • On each succeeding turn, the player subtracts any two marked numbers to find and mark a difference that has not yet been taken.
  • Play alternates until no more numbers can be marked.

Continue reading Euclid’s Game on a Hundred Chart

2008 Mathematics Game

Are you ready for a challenge? Join us for the 2008 Mathematics Game. Here are the rules:

Use the digits in the year 2008 and the operations +, -, x, ÷, sqrt (square root), ^ (raise to a power), and ! (factorial) — along with parentheses, brackets, or other grouping symbols — to write expressions for the counting numbers 1 through 100.

  • All four digits must be used in each expression.
  • Only the digits 2, 0, 0, 8 may be used.
  • Multi-digit numbers such as 20, 208, or .02 MAY be used this year.
  • The square function may NOT be used.
  • The integer function may NOT be used.

By definition:
0! = 1
[See Dr. Math’s Why does 0 factorial equal 1?]

For this game we will accept the value:
{0}^{0} = 1
[See the Dr. Math FAQ 0 to the 0 power.]

Continue reading 2008 Mathematics Game

Puzzles for the New Year

by Koshyk via flickr

As we all head back to school, here are some interesting calendar puzzles:

  • 2008 is a leap year. Why do leap years happen? If we didn’t add a leap day every so often, would January eventually come in the summer?
  • Today is Thursday. What day of the week will it be exactly one year from today?
  • January 1, 2008, came on a Tuesday. When will be the next year that begins on Tuesday?
  • My birthday (in March) lands on a Monday this year. When is the next year my birthday will come on a Monday? How about YOUR birthday — when is the next time it will happen on the same day of the week as this year?
  • Can you find a pattern in the way dates move from one day of the week to another, year after year?

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Leon’s Christmas Gift

Lo-shu turtle

Here is the simplest puzzle from the November/December 1998 issue of Alexandria Jones stories. The answer (and more puzzles) will follow.

Christmas gift for Leon (pdf, 68KB)

Edited to Add

More puzzles are now here:

Magic square puzzles

Answers are also posted:

Christmas puzzle answers

To Be Continued…

Read all the posts from the November/December 1998 issue of my Mathematical Adventures of Alexandria Jones newsletter.

Christmas Math Puzzles and Activities

by HikingArtist.com via flickr

UPDATE: Some of the links below have gone missing, as internet sites tend to do. Check out my *huge* new blog post:

We interrupt our regularly scheduled math program to bring you the following Christmas links…

First, A to Z Home’s Cool offers some fun for older students and teachers:

Also check out the annual Price of Christmas Index to see what the “12 Days of Christmas” gifts would cost you this year. Or explore the Nrich Advent Math Calendars to play with a new math activity every day until Christmas.

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

Continue reading Christmas Math Puzzles and Activities