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?

Click here for all the mathy goodness!

Do You Blog About Math?

It’s carnival time again. Activities, games, lessons, hands-on fun — if you’ve written a blog post about math, we’d love to have you join our Playful Math Blog Carnival.

Posts must be relevant to students or teachers of school-level mathematics (that is, anything from preschool up through first-year calculus). Old posts are welcome, as long as they haven’t been published in past editions of this carnival.

Click here to submit your blog post

Don’t procrastinate: The deadline for entries is Sunday, November 25. But if you wait that long, you’ll forget. So send in your submission today!

Have you noticed a new math blogger on your block that you’d like to introduce to the rest of us? Feel free to submit another blogger’s post in addition to your own. Beginning bloggers are often shy about sharing, but like all of us, they love finding new readers.

Need an Idea-Starter?

If you haven’t written anything about math lately, here are some ideas to get your creative juices flowing…

  • Talking Math with Kids: Children often have surprising insight. Even when they’re confused about math, their point of view can open our adult eyes to new understanding. Share your kids’ stories.
  • Games or Activities: Do you have a game, activity, or anecdote about teaching math to young students? We’d love to play along.
  • Lesson Ideas: This section is for arithmetic explorations, geometry puzzles, trig investigations, contest-preparation tips, and more. Can you make math topics come alive, so they will stick in a student’s mind?
  • Teaching Tips: Other teachers’ blogs are an important factor in my continuing education. The more I read about the theory and practice of teaching math, the more I realize how much I have yet to learn. So please, fellow teachers, don’t be shy — share your insights!
  • Mathematical Recreations: What kind of math do you do, just for fun?

Explore the Other Math Carnivals

While you’re waiting for next week’s carnival, you may enjoy:


CREDITS: “Two Bloggers, after Norman Rockwell” sketch (top) by Mike Licht (CC BY 2.0) via Flickr.

howtosolveproblemsWant to help your kids learn math? Claim your free 24-page problem-solving booklet, and sign up to hear about new books, revisions, and sales or other promotions.

Playful Math Carnival 122 at Arithmophobia No More

Check out the latest carnival of playful math for all ages:

Each monthly Playful Math Education Blog Carnival brings you a great new collection of puzzles, math conversations, crafts, teaching tips, and all sorts of mathy fun.

It’s like a free online magazine of mathematical adventures. Enjoy!

Sonya put together this carnival of evergreen links — helpful and inspiring no matter when you read them — featuring math comics, a couple conversations on Euler, Truchet and infinity tiles, Islamic art, counting and counting ropes, negative numbers, and more.

Click Here to Read the Carnival Blog

Want to Join in the Fun?

Do you have a favorite blog post about math activities, games, lessons, or hands-on fun? The Playful Math Blog Carnival would love to feature your article!

We welcome math topics from preschool through the first year of calculus. Old posts are welcome, as long as they haven’t been published in past editions of this carnival.

To submit a blog article for consideration, fill out this form:

Yes! Please Share My Post

Have you noticed a new math blogger on your block that you’d like to introduce to the rest of us? Feel free to submit another blogger’s post in addition to your own. Beginning bloggers are often shy about sharing, but like all of us, they love finding new readers.


howtosolveproblemsWant to help your kids learn math? Claim your free 24-page problem-solving booklet, and sign up to hear about new books, revisions, and sales or other promotions.

Playful Math Education Carnival 121 at nebusresearch

Check out the new playful math blog carnival at nebusresearch blog. Joseph put together a great collection of math games, activities, and teaching tips:

The carnival features classic puzzles, geometric art, Friedman numbers, scrambled times tables, mathematical comics, the friendship paradox, and a free online topology game. And much more — too many topics to list!

A few of the entries may push the limits of “school level” math, but there’s plenty of mathy fun to go around.

Click here to go read the carnival blog

And if you’re a blogger, be sure to submit your blog post for next month’s carnival!

Past carnivals are still full of mathy treasure. See them all on Pinterest:


CREDITS: Carnival photos (above) by Casey Horner and reyhan afif on Unsplash.

howtosolveproblemsWant to help your kids learn math? Claim your free 24-page problem-solving booklet, and sign up to hear about new books, revisions, and sales or other promotions.

Playful Math Carnival 120 at Find the Factors

Check out the latest carnival of playful math for all ages:

Each monthly Playful Math Education Blog Carnival brings you a great new collection of puzzles, math conversations, crafts, teaching tips, and all sorts of mathy fun. It’s like a free online magazine of mathematical adventures. What fun!

Iva Sallay put together this carnival of evergreen links — helpful and inspiring no matter when you read them.

This carnival offers math art and poetry, kid-made books, journaling, logic, and talking math with kids. Same and Different, How Many, and other puzzles. And more!

Click Here to Read the Carnival Blog

Want to Join in the Fun?

Do you have a favorite blog post about math activities, games, lessons, or hands-on fun? The Playful Math Blog Carnival would love to feature your article!

We welcome math topics from preschool through the first year of calculus. Old posts are welcome, as long as they haven’t been published in past editions of this carnival.

To submit a blog article for consideration, fill out this form:

Yes! Please Share My Post

Have you noticed a new math blogger on your block that you’d like to introduce to the rest of us? Feel free to submit another blogger’s post in addition to your own. Beginning bloggers are often shy about sharing, but like all of us, they love finding new readers.


CREDITS: “One Galaxy” drawing by Sara Divenuto, age 10, via Hubble Space Telescope / ESA on Flickr (CC BY 2.0).

howtosolveproblemsWant to help your kids learn math? Claim your free 24-page problem-solving booklet, and sign up to hear about new books, revisions, and sales or other promotions.

Playful Math Education Carnival 119 at Three J’s Learning

Check out the new playful math blog carnival at Three J’s Learning blog. Joshua put together a great collection of math games, activities, and teaching tips:

The carnival features a “square dancing” puzzle, strategy game discussions, divisibility rules, fake theorems, and mathematical oceans in disguise. And much more!

Click here to go read the carnival blog

And if you’re a blogger, be sure to submit your blog post for next month’s carnival!

Past carnivals are still full of mathy treasure. See them all on Pinterest:


CREDITS: Carnival photos (above) by Scott Trento and Craig Smith on Unsplash.

howtosolveproblemsWant to help your kids learn math? Claim your free 24-page problem-solving booklet, and sign up to hear about new books, revisions, and sales or other promotions.