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Have you and your students enjoyed a project, game, or handout from my blog? If you would like to say "Thank you," then consider buying yourself that book you've been meaning to read...Math Teachers At Play #10 is now posted…
Today is the last day to send in your submission to the next Math Teachers at Play blog carnival, which will be posted this Friday at Homeschool Math Blog.
I am still trying to catch up on priorities at home, so I don’t know when I’ll be back to blogging. After Maria’s carnival this Friday, we don’t have another host scheduled until August. Would anyone like to volunteer, or shall we take a break for the summer?
My Internet connection has been like a yo-yo: up and down, but mostly down. DH — who has little patience for blogging — says that’s just as well, because my main job this summer needs to be a major decluttering and housecleaning project. So I’ll be back when I can, but I don’t know how soon…
In the meantime, check out the Carnival of Mathematics #53. And be sure to send in your entry for this week’s Math Teachers at Play blog carnival, to be published this Friday at Homeschool Bytes.
[Edited to add: Math Teachers at Play #9 - Game Time! now posted. Enjoy!]
[Photo by jaaron.]
Welcome to the Math Teachers At Play blog carnival — which is not just for math teachers! We accept entries from anyone who enjoys playing around with math, as long as the topic is relevant to students or teachers of preK-12th grade mathematics.
Some articles were submitted by their authors, other were drawn from the back-log in my blog reader, and I’ve spiced it all up with a few math jokes courtesy of the Mathematical humor collection of Andrej and Elena Cherkaev.
Let the mathematical fun begin…
ELEMENTARY CONCEPTS
[Photo by David Mezzo Van Couvering.]
Q: How do you tell that you are in the hands of the Mathematical Mafia?
A: They make you an offer that you can’t understand.
- If you don’t know how to interpret this photo, check out Now THAT is the way to learn math, where David Van Couvering writes about how his daughter learned the times tables at her Waldorf School.
- For several great ideas about teaching math to young children, check out this classic post: Math the Play Way.
- It looks to me like Amy Lapain and her son are having a lot of fun with Crazy Math. Amy explains, “My son has ADHD, but when I write out practice sheets like this it actually helps him focus.”
- “Next time you need to teach about math with money, budgeting, and keeping a running total,” says Misty, “look no further than your next shopping trip. Turn the whole thing over to your child and let them learn how they need all that math in the ‘real world’.” Check out the way she Gives Kids Money and a Budget.
- Without venturing into the “real world,” Jimmie stages a shopping trip to let her daughter play around with Hands-on Estimating.
ARITHMETIC
[Photo by jimmiehomeschoolmom.]
According to statistics, there are 42 million alligator eggs laid every year. Of those, only about half get hatched. Of those that hatch, three fourths of them get eaten by predators in the first 36 days. And of the rest, only 5 percent get to be a year old for one reason or another. Isn’t statistics wonderful? If it weren’t for statistics, we’d all be eaten by alligators!
- Heather presents a great way to integrate all kinds of problem solving in your math program by Math Journaling.
- Lefty shares an interesting set of problems in Math problems of the week: 3rd grade Everyday Math vs. 1920s Math. Or if 3rd grade is to easy for your students, try giving them these: Math problems of the week: 6th grade Connected Math vs. Singapore Math.
- Here is something my daughter would love — using algebra to learn arithmetic! Mr. L describes how Schools Turn Algebra into Child’s Play in Lebanon, Oregon.
- I haven’t had time to sit at the computer and write recently, so here’s a treat from the archives for my carnival entry: Putting Bill Gates in Proportion.
- Not sure whether your students have fully mastered the basics? Dan Greene offers a review of arithmetic with his Numeracy Curriculum.
BASIC ALGEBRA & GEOMETRY
[Photo by John-Morgan.]
One evening Rene Descartes went to relax at a local tavern. The tender approached and said, “Ah, good evening Monsieur Descartes! Shall I serve you the usual drink?”
Descartes replied, “I think not.”
— and promptly vanished.
- Child’s Play continues an excellent series on the mathematics of circles with Math Monday: Trampoline Math!
- Nick Hershman offers an updated set of lessons about Systems of Equations/Inequalities.
- Jonathan explores a variety of transformations in Teaching off topic 4. Joshua Fisher gives the topic a twist in 45 Degree Rotations About the Origin.
- Have you ever wondered how people ever managed to calculate Square roots with pencil and paper? Brent Yorgey explains the Babylonian method.
- John Cook explores a few more tidbits about the golden ratio in Golden ratio and special angles.
ADVANCED MATH
[Photo by thejonoakley.]
“Do you love math more than me?”
“Of course not, dear – I love you much more.”
“Then prove it!”
“OK… Let R be the set of all lovable objects…”
- My students have been enjoying (or, as Chickenfoot would put it, “suffering through”) a few of Dave Marain’s challenge problems: Classic Exponent Challenge for SATs, Algebra 2, Math Contests, and A Recurring Problem for SATs (Functions).
- Alexander MacLane clears up some troublesome Max/Min Terminology for calculus students.
- Robert Talbert shares insight gained from 16 years of teaching experience in Four things I used to think about calculus, and what I’ve replaced them with.
- How would you like to experience mathematical vertigo? Check out the film series Dimensions.
- Mark C. Chu-Carroll warns us that You can’t write that number; in fact, you can’t write most numbers.
- Does anyone know where the Carnival of Mathematics has gone this time? [Update: It will be here next Friday.]
MATHEMATICAL PUZZLES
[Photo by fdecomite.]
Boring Theorem:
All positive integers are boring.Proof:
Assume the contrary. Then there is a lowest non-boring positive integer. Who cares!
- Dana shares the fun of playing with Soma Cubes, one of my all-time favorite 3-D puzzles. If you’d like to try making your own set, look at History of Soma Cube, which describes the basic blocks and includes plenty of puzzles.
- For a wide variety of challenges from the American Mathematics Competitions, check out MAA MinuteMath.
- Pat Ballew remembers some of the giants upon whose shoulders we all stand in Logic Diagrams, A Brief History.
- Speaking of logic puzzles, could you reason your way to freedom if you were one of 4 Buried Soldiers?
- And don’t forget to send in your solution to Monday Math Madness #33: Prime Factorization this weekend!
ABOUT TEACHING MATH
[Photo by chrisrobinson1945.]
“The number you have dialed is imaginary. Please rotate your phone 90 degrees and try again.”
“What’s your favorite thing about mathematics?”
“Knot theory.”
“Yeah, me neither.”“In modern mathematics, algebra has become so important that numbers will soon only have symbolic meaning.”
- Maria Miller presents Homeschool Math Blog: Lockhart’s Lament, saying, “This is an old post — an inspirational example of a math problem where one is able to ‘create a profound simple beauty out of nothing’.”
- Find out how several teachers answer the question, “Do You Analyze Student Work to Improve Your Teaching?”
- Dan tells us about an intriguing, inexpensive method to boosts kids’ test scores…and an expensive remedy that doesn’t really work like you might think: Things that Make your Kids Smarter…and Things that Don’t.
- Jason Dyer revisits last summer’s hot topic of controversy in The “Multiplication is Not Repeated Addition” Research.
- Have you started planning for next year yet? Lara DeHaven reviews the free Mathematics Enhancement Programme in My Math Curriculum Pick.
And that rounds up this edition of the Math Teachers at Play carnival. I hope you enjoyed the ride.
The next installment of our carnival will open on June 12 at Homeschool Bytes. If you would like to contribute, please use this handy submission form. Posts must be relevant to students or teachers of preK-12 mathematics. Old posts are welcome, as long as they haven’t been published in past editions of this carnival.
Past posts and future hosts can be found on our blog carnival index page.
We need more volunteers. Classroom teachers, homeschoolers, unschoolers, or anyone who likes to play around with math (even if the only person you “teach” is yourself) — if you would like to take a turn hosting the Math Teachers at Play blog carnival, please speak up!
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If you blog about learning or teaching math, be sure to send in your submission to the Math Teachers at Play blog carnival. Tomorrow is the deadline for this week’s edition.
[And if you've been wondering: Yes, I will get back to blogging, someday. Hubby laid down the law, so Spring Cleaning is the priority these days. I hate housework! But I am making progress, a little at a time....]
[Photo by rick.]
The math is sizzling at Homeschool Bytes with the Math At Play Blog Carnival — Onomatopoeia Edition. There is something for everyone, from elementary multiplication and division to exponential functions and geometric series. Check it out!
And while you’re playing around with math, don’t forget the Carnival of Mathematics #52, which went up last week at The Number Warrior. Plenty of fun there, too. Does anyone know where the next one will be?
There is also the Carnevale Della Matematica # 13. (Google’s attempt at translation.)
[Hat tip: The Number Warrior.]
I’m still looking for more hosts to help out with the Math Teachers at Play carnival. If you’d like to give it a try, check out the carnival schedule and pick a date that works for you.
[Photo by Flavinsky Photography.]
Dave Marain has extended the deadline for entering his MathNotations Second Math Contest to this Friday, May 15th. The first contest was a lot of fun for my math club, and I am looking forward to this new one. You can see a (relatively easy) example problem here — although I wouldn’t be surprised to find something more like this on the contest itself. If you teach high school students, check it out!
Also, now is the time for all teachers, homeschoolers, and anyone else who enjoys playing around with K-12 mathematics to send in your favorite blog posts for the next Math Teachers at Play blog carnival. The deadline is Wednesday, May 13th, and the carnival will be posted on Friday at Homeschool Bytes.
For more education-related blog carnivals, be sure to check Blog Parties for Teachers widget in my sidebar. I just updated it this morning with the new Carnival of Homeschooling and the Monday Math Madness post, among others. Enjoy!

[Ragged Squares Quilt photos used with permission from Crazy Mom Quilts.]
I know other teachers have done math quilts, but I’ve never gotten around to trying it in any of my classes. Still, this image caught my eye and practically begged me to make it into a math lesson for my elementary math club.
I thought of at least two ways I could go with this, but I bet that if we put our brains together, we can come up with even more creative ideas. So here’s the question, ala Dan Meyer:
- What can you do with this?
How could you use this image as a springboard to doing math? What questions would you ask? What concepts would you try to get across? What would you follow it with? Please comment!
Other photos are available…
The Carnival of Mathematics #52 is up and running at The Number Warrior, with tidbits about perfect numbers and Mersenne primes as well as links to a variety of interesting blog posts. Even if you aren’t a particularly “mathy” person, I think you will enjoy these:
- The federal budget, rescaled
- The Pattern Does Not Hold
- What’s the Chance That the Patient Has the Disease?
Check out the rest of the articles at Carnival of Mathematics #52.
And if you didn’t catch it last week, Math Teachers at Play #6 was short but fun at I Want to Teach Forever. Next week’s Math Teachers at Play carnival will be hosted by Misty at Homeschool Bytes. If you blog about math on the K-12 level, be sure to send in your entry soon!
[Update: This workbook is no longer free, but it will remain on sale at a 25% discount until May 15th.]
Today (Wednesday, May 6) only, you can download a free copy of Make It Real Learning: Arithmetic I, a 46-page workbook for grades 3-6:
The Arithmetic I workbook focuses on real-world situations that may be effectively analyzed using arithmetic concepts such as addition, subtraction, estimation, division, bar graphs, etc. From figuring out how to determine the difference between the populations of two countries to analyzing the number of visitors to a website, learners get to use arithmetic in meaningful ways. Rest assured that each activity integrates real world information not just “realistic” data. These are real companies and countries (e.g. Webkinz, Australia, South Africa) and real world issues.
More information:
- Review of Make It Real workbooks
- Free download of sample activities (all levels: arithmetic through calculus)
Y of x reminded me about one of my old favorite websites for math fact practice with a purpose:
5-10 minutes of daily practice will cement the math facts in your student’s mind, while at the same time doing a good deed. For each correct answer, a Free Rice sponsor donates a very small amount of rice to feed hungry people worldwide through the UN World Food Program.
Even very small amounts of rice add up. Since Free Rice started in 2007, its sponsors have bought more than 63 billion grains of rice, just by paying for one right answer click at a time.
You and your students can practice other topics as well:
According to a MathCounts press release, you can tune in this Friday, May 8, to watch the 2009 Raytheon MATHCOUNTS National Competition live:
Once again, MATHCOUNTS will present the 2009 Raytheon MATHCOUNTS National Competition, live via web cast on www.mathcounts.org. On Friday, May 8th at 2:00 PM EDT, you’ll have the opportunity to watch the nation’s most talented middle school mathematicians compete against each other in a battle of the buzzers!
Meanwhile, this year’s local, chapter, and state competitions are available. [Beware: A few of the files have the “doc” extension, but they are all pdf Download them for yourself, and start studying for next year!

[Map as of early afternoon on May 4th, found at the NY Times.]
Compare the dark circles (confirmed cases) for Mexico, New York and Nova Scotia in the top part, or Mexico and the U.S. in the lower part of the map. It’s easy to see which has more cases of the flu — but how many more? Which would you guess is the closest estimate:
Mexico : New York : Nova Scotia
- = 7:3:2 or 20:5:3 or 16:2:1?
U.S. : Mexico
- = 1:2 or 2:5 or 3:7?













