## Archive for April, 2010

### Math Poems

I posted a math poem two days ago. Here are a few more that I love (though I’m probably breaking some copyright laws by posting them… oh, well, math humor is meant to be shared):

Pi goes on and on and on,

and e is likewise cursed…

I wonder which is longer when the digits are reversed?

A mathematician confided,

A Mobius strip is one-sided.

You’ll get quite a laugh,

When you cut one in half,

For it stays in one piece when divided.

### Cats and Dogs

This joke makes it easy to see how teachers sometimes inadvertently confuse students…

Teacher: If I give you two dogs and then give you two more dogs, how many dogs will you have?

Johnny: Five!

Teacher: Not quite. Try again. If I give you two dogs and then give you two more dogs, how many dogs will you have?

Johnny: Five!

Teacher: Hmm, no. Let’s try this another way. If I give you two cats and then give you two more cats, how many cats will you have?

Johnny: Four.

Teacher: Excellent! So, if I give you two dogs and then give you two more dogs, how many dogs will you have?

Johnny: Five!

Teacher: I don’t understand! Why do you say that if I give you two cats and then two more cats, you’ll have four, but if I give you two dogs and then two more dogs, you’ll have five?

Johnny: Because we’ve got a dog at home!

My colleagues and I used to joke about the LCS teaching method. Don’t be embarassed if you’re a veteran teacher but have never heard of this method before. We made it up. The acronym LCS stands for Louder, Closer, Slower. There was, unfortunately, one teacher in our school who, if a student didn’t understand an explanation, would say the exact same thing over and over… but each time would move closer to the child, say the words in a louder voice, and speak more slowly.

It was difficult to watch these interactions. With each repetition of the explanation, the teacher would get more and more frustrated. Sadly, the student would get further frustrated, too, but the teacher would never notice! It was like watching an American tourist in France ask for directions!

Happily, I know that the majority of math teachers don’t abide by that method, so here’s a math poem for all you great teachers–

He’s teaching her arithmetic,

Because it is his mission.

He kissed her once, he kissed her twice

and said, “Now, that’s addition.”As he added smack by smack

In silent satisfaction,

She sweetly gave the kisses back

and said, “Now, that’s subtraction.”Then he kissed her, she kissed him,

Without an explanation,

And both together smiled and said,

“Now, that’s multiplication.”Then Dad appeared upon the scene and

Made a quick decision.

He kicked the boy out of the house

And said, “Now, that’s division!”

### Success at NCTM Annual Meeting!

**Math Jokes 4 Mathy Folks** sold out at the NCTM Annual Meeting! It was offered in the NCTM Bookstore, where members received a 25% discount off the cover price. Officially, the conference started on Thursday morning, but the bookstore was open on Wednesday, and all 250 copies were sold by Wednesday afternoon. Thanks to everyone who bought a book! (Members who weren’t able to get a copy at the conference can call (800) 235-7566 to order a copy from NCTM. For large orders, call Robert D. Reed publishers at (541) 347-9882 to inquire about bulk discounts.)

I did a book signing yesterday afternoon — my first ever. It was a lot of fun! It was both exciting and intimidating to see a long line of fans waiting when I arrived, but I had a great time talking to them and sharing jokes (full story on NCTM.org). One woman shared a joke I’d heard before:

What type of lingerie does a mermaid wear? An algae-bra!

But she had a follow-up that was new to me:

What type of lingerie does a little mermaid wear? A pre-algae-bra!

It was great to get some new material.

Thanks to everyone for your incredible support! A big thanks to anyone who shared a joke with me, and an especially huge thanks to members of the NCTM marketing department who made this all possible!

### Make Your Own (Math) Joke

Here’s my favorite joke (even though it’s not a math joke):

Two cannibals are eating a clown. One turns to the other and says, “Does this taste funny to you?”

It’s beautiful in its simplicity. Just 19 words, none of them extraneous. It’s a triumph of humor, and I tip my hat to its creator.

I love this joke, and I would have included it in *Math Jokes 4 Mathy Folks*, but it’s not a math joke. But it got me to thinking — could it be altered so that it could be a math joke? That is, can you put two different words in the blanks below so the joke is more mathy? And can you do it so that it’s still reasonably funny?

Two cannibals are eating a ________. One turns to the other and says, “Does this taste ________ to you?”

I offered this challenge to attendees at the Math Joke Hour that I hosted yesterday at the 2010 NCTM Annual Meeting. They came up with quite a few that are worth sharing, though not all of them are mathematical:

math teacher… chalky

statistician… normal

Kenneth Appel… fruity*

actuary… bland

angel… heavenly

mechanic… greasy

Iowan… corny

pot smoker… mellow

Warren Buffett… rich

old seafarer… salty

bodybuilder… strong

Got another worth sharing? Leave it in the comments section.

* Kenneth Appel is the mathematician who, along with Wolfgang Haken, proved the Four Color Theorem in 1976.

### Venn Diagram for April

Are you aware that April is Math Awareness Month?

And did you know that April is also National Humor Month?

Those two things mean that:

- This is a great time for me to present the Math Joke Hour at the 2010 NCTM Annual Meeting in San Diego, April 21‑24. The Math Joke Hour will be held Wednesday, April 21, at 2:30pm in Room 6E of the San Diego Convention Center. Hope to see you there!
- It’s an even better time to buy Math Jokes 4 Mathy Folks! You can purchase it directly from Robert D. Reed Publishers; or, if you’re attending the NCTM Annual Meeting in San Diego, you can pick up a copy in the bookstore at a 25% discount.

### NCTM Annual Meeting — San Diego

The NCTM Annual Meeting will be held April 21-24 in San Diego. On behalf of the Council, I’ll be presenting the following sessions:

**Math Joke (Half) Hour**Wednesday, April 21, 2:30-3:00pm; Convention Center, Room 6E

(if there’s enough interest, this session will be repeated at 3:15pm in the same room)**Online Math Strategy Games for the Middle School Curriculum**Saturday, April 24, 8:30-10:00am; Convention Center, Room 15A

When not presenting, I’ll be hanging out in the Cyber Cafe (within the exhibit hall), telling folks about all the great classroom resources they can find at Illuminations and Calculation Nation^{TM}. Stop by to say hello — and to tell me your favorite math joke!

### Tax Day

Income tax is due today. Here’s a good, clean joke for April 15:

A nickel rolled down the hill. Why didn’t the quarter follow her?

Because it had too much cents!

### April 15 is National High Five Day

The third Thursday of April is National High Five Day. In 2010, that’s today! Normally, I ignore made up holidays like this, but there are (at least) two great math problems that involve high fives. So if acknowledging a silly fabrication means I get to share some math, then I’m all for it.

Here are the problems I know related to high fives:

There are five players on a basketball team. When the star player hit the winning free throw at the end of regulation, she and each of her teammates gave each other a high five. How many high fives occurred?

You could also ask this question in the opposite direction (though it’s really the same question):

My friends and I were watching a Penn State football game. When Penn State kicked the winning field, my friends and I gave each other high fives. Each friend gave exactly one high five to every other friend. A total of 36 high fives occurred. How many friends were watching the game with me?

But, in my opinion, here is the best variation of this problem:

My wife and I play on a softball team with four other couples. After I hit the game-winning home run at a recent game, a lot of high fives occurred among the players on our team. But not everyone got a high five from everyone else, no one got a high five from his or her spouse, and — obviously — no one high fived himself. Later, I asked each of my teammates how many high fives they received, and everyone gave me a different response. How many high fives did my wife get?

Now, don’t you agree that those questions make celebrating National High Five Day a reasonable thing to do?