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Math Teachers at Play #28 via CTK Insights

There’s plenty to enjoy at this month’s Math Teachers at Play blog carnival. Check it out:

This is a Math teachers at play carnival, issue #…which I am going to reveal shortly. See if you can make it from what is known as a single image stereogram. Try focusing your eyes behind the screen.

In this month’s issue: What is the number of this issue? … Sad news … Interesting and relevant news … From the trenches … Math curiosities … Jokes … P.S. … Read more

via CTK Insights

Mathematics and Multimedia Blog Carnival #1

The new math carnival is up, and it’s a good one. Check it out!

Also, remember that Wednesday’s the deadline to send in your submission for the Math Teachers at Play carnival, coming this Friday now posted at CTK Insights.

Mathematics and Multimedia Blog Carnival #1 THE NUMBER 1 Welcome to the Mathematics and Multimedia Blog Carnival Number 1. Before beginning, let us see what's so special about 1 as a number. is a homophone of Juan (dela Cruz), the person who represents the Filipino people.  He is just like Uncle Sam of the United States. Hmmm… just a thought, should we change Juan dela Cruz to Manny Pacquiao? is the multiplicative identity. Any number multiplied by 1 is equal to that number. is the only … Read More

via Mathematics and Multimedia

Congratulations, Kitten!

[Photo by dougwoods.]

Today is my daughter Princess Kitten’s blogiversary. Check out her post:

And then take some time to browse her blog. I think you’ll enjoy her stories. She’s even written a few things about math:

[Update: I just noticed that this is the 500th post to be published on Let’s Play Math! blog. Wow! I guess Kitten and I will both be celebrating today…]

Rate Puzzle: How Fast Does She Read?


[Photo by Arwen Abendstern.]

If a girl and a half
can read a book and a half
in a day and a half,
then how many books can one girl read in the month of June?

Kitten reads voraciously, but she decided to skip our library’s summer reading program this year. The Border’s Double-Dog Dare Program was a lot less hassle and had a better prize: a free book! Of course, it didn’t take her all summer to finish 10 books.

How fast does Kitten read?

Continue reading Rate Puzzle: How Fast Does She Read?

How To Host a Blog Carnival

[Photo by ell brown.]

Update March 2012

The blog carnival website has been unreliable for several months, which is why you will see strike-through on the paragraphs below that deal with that site. Please read the current information on these pages:

Do you want your blog to grow? One of the best ways to draw new readers to your blog is to get involved in an active blog carnival. Mike wrote an excellent article (What is a Maths Carnival?) explaining how carnivals work and how to submit an entry.

Now, if you’re ready to raise the ante a bit, let’s bring the carnival itself to your blog.

These instructions are specifically about the Math Teachers at Play (MTaP) blog carnival for classroom teachers, homeschoolers, and independent math learners. After all, that’s the carnival I know best. Still, most of the principles should apply to any blog carnival you might want to host.

Continue reading How To Host a Blog Carnival

How To Start a Math Teacher Blog

[“Sophisticated Blogger” by Mike Licht, NotionsCapital.com.]

Blogging is more than just writing. It involves reading other people’s blogs and commenting, comparing thoughts about mathematics and ideas for teaching it, even getting involved in debates like the multiplication is or isn’t repeated addition kerfluffle. In a way, the blogging community acts like the Chinese “teaching research groups” mentioned in Liping Ma’s book, Knowing and Teaching Elementary Mathematics.

What a coincidence! I wrote that paragraph last week for Math Mama’s book, and then this weekend I opened my backlogged rss reader to discover a series of posts from some of my favorite math bloggers offering excellent advice on how to start a blog.

If you are a classroom teacher, homeschooler, or independent math learner who would like to get into blogging, check out these posts. And if you’re an experienced hand, please add your favorite blogging tips in the Comments section below.

Continue reading How To Start a Math Teacher Blog

Math Teachers at Play #27 via Math Mom


The carnival is up at Ramblings of a Math Mom, a day late but well worth the wait:

Mathmom herself wrote a wonderful post for the carnival, which I was glad to see. I’ve missed her!

You May Also Enjoy

Here’s a puzzle I found to fritter away time while I was waiting for the carnival:

[Warning: The answers are in the same blog post, so don’t scroll down until you’ve tried the puzzle!]

Hobbit Math: Elementary Problem Solving 5th Grade

[Photo by OliBac. Visit OliBac’s photostream for more.]

The elementary grades 1-4 laid the foundations, the basics of arithmetic: addition, subtraction, multiplication, division, and fractions. In grade 5, students are expected to master most aspects of fraction math and begin working with the rest of the Math Monsters: decimals, ratios, and percents (all of which are specialized fractions).

Word problems grow ever more complex as well, and learning to explain (justify) multi-step solutions becomes a first step toward writing proofs.

This installment of my elementary problem solving series is based on the Singapore Primary Mathematics, Level 5A. For your reading pleasure, I have translated the problems into the world of J.R.R. Tolkien’s classic, The Hobbit.

UPDATE: Problems have been genericized to avoid copyright issues.

Continue reading Hobbit Math: Elementary Problem Solving 5th Grade