Friday, October 20, 2023

Mole Day!

Mole and Tell (Celebrating Science)
by Catherine Payne and John Payne; illus. by Elisa Rocchi
40 pages; ages 7-10
Science, Naturally!, 2023

What’s that date written on the board?

When the students file into Mr. Cantello’s fourth-grade science class, they notice a date written on the board: 10/23. What does it mean? Is it a field trip? A test? Maybe it’s Earth Day? Not Earth Day, Mr. Cantello says, but it is a science holiday. It’s Mole Day, October 23.

Is this a day to celebrate spots on our skin? To celebrate tiny animals that tunnel underground? Nope. It’s a celebration of a number. Avogadro’s number, to be exact: 6.02 x 1023. It’s a counting unit used by scientists all around the world. Sort of like a dozen, but instead of 12, a mole is 602 billion trillion. That’s 602 followed by 21 zeroes! Scientists write it as 6.02 x 10 to the 23rd because seriously, writing 602,000,000,000,000,000,000,000 every time you need to use it takes up too much space!

What I like about this book: I think the authors do a good job introducing the concept of a mole. And having a group of kids explore what a mole of something is might encourage readers to wonder. There’s some discussion of elements, and an illustration that shows the periodical table along with molar mass (the number of grams in a mole of an element), plus a discussion about the kinds of scientists who use moles to measure things in their jobs. I do wish there had been a sidebar explaining more about who Avogadro was and how he (and others) developed this measurement.
I wanted to know more about how Cathy and John decided to write this book, so I asked Cathy One Question:
Me: What inspired you to write about such a big number?

Cathy: I've been fascinated by the mole since learning about it in my high school chemistry class. In addition, I love homonyms! This book was the perfect way to combine my love of language with my interest in science. For this book, we focused on breaking down scientific concepts, explaining the mole and the periodic table as best we could. We wanted children to have a solid understanding of the mole so that they would have a good foundation for units of measurement.

There isn’t any back matter beyond a glossary, but Science Naturally provides an activity-filled teacher’s guide at their website. I’ve added a few more activities below at…

… Beyond the Books:

How much would a mole of avocados weigh? Cathy admits she likes to play with language, so why not? Since 6.02 x 1023  is Avogadro’s number, why not play around with avocados? You can even weigh one (or more) right there in the produce aisle.

Mole Day is next Monday. What kind of food will you make to celebrate? Here’s a couple of ideas to get you started: guaca-mole, pie a’la mole, ani-mole crackers.

Go play a game of whack-a-mole. If you can’t find one (because it IS an ancient and venerable arcade game) try making your own out of cardboard. Here’s how.

Make up your own Science Holiday. What science thing do you want to celebrate? 

Thanks for dropping by today. On Monday we'll be hanging out at Marvelous Middle Grade Monday with other  bloggers. It's over at Greg Pattridge's blog, Always in the Middle, so hop over to see what other people are reading. Review copy provided by the authors.


  1. Thanks for this post! I hope that everyone enjoys Mole Day! The mole, the merrier!

  2. Sounds like a fun book. Happy MMGM to you

  3. Great way to excite kids about science with moles taking center stage. Thanks for featuring your post on this week's MMGM.

  4. The title of this book and the activities all sound great. Thanks for the review. Happy Mole Day--belatedly. Carol Baldwin

  5. This sounds like a fun book that I could learn from. I never heard of Mole Day before.

  6. This sounds fun. It's always nice to find books that will engender kids to dip their toes into science. Thanks for the review.

  7. This sounds such a fun way to introduce & explain a theoretical concept! Belated happy Mole Day!

  8. How fun! I love when authors find ways to make scientific concepts really accessible to kids.