One of my favourite read alouds is One Is a Snail, Ten Is a Crab. In April Pulley Sayre’s “counting by feet book,” one is a snail, two is a person, four is a dog, six is an insect, eight is a spider, and ten is a crab.
The odd numbers to nine and multiples of ten to one-hundred are represented as combinations of animal feet. For example, three is a person and a snail; ninety is nine crabs or ten spiders and a crab.
Last week, Sandra and I visited a Grade 1 classroom in which we asked “How many different ways can you make ten?” Children read a number sentence (e.g., “six and four make ten”) to go with each of their drawings. Some students built the animals using muli-link cubes. Some students wrote addition equations (e.g., 6 + 4 = 10). There were multiple approaches to solving this problem. For example, this student skip counted by twos (I think).
These two students used the ten-fact pair of eight and two to make ten. Ten is a crab and a person (8 + 2) but this can be partitioned further as two snails and two dogs (1 + 1 + 4 + 4) or two dogs and a person (4 + 4 + 2).
Another student (sorry, no photo) broke up ten as five and five and then five as four and one; he drew a dog and a snail twice (4 + 1 + 4 + 1).
These solutions reflect an understanding of “ten-ness.” These students are not (just) counting feet. Gotta be the ten-frames.
It is important to provide opportunities for children to think about numbers as compositions of other numbers. Breaking up numbers, into tens and ones or in other ways, makes computations easier in later grades.
Click here for more math picture book (picture book math?) ideas.
Thanks to Ms. Long and the young mathematicians at Fraser Wood Elementary for inviting us into your classroom. Also, thanks to Pete Nuij and Lesley Tokawa for helping make this happen.
Chris Hunter 
Fabulous story!! Thank you for sharing it. Am meeting with a kindergarten team on Thursday and would like to share your post and your thinking. Thanks.
I too love this story for teaching math. Last week I read it to my grade 1’s and 2’s and they built their combinations using the cuisenaire rods. For example, 1 crab (orange rod) and 10 people (red rods). Someone made 12 as one crab, and two snails (using orange rod and two white rods). They had a great time using the rods to show the number combinations.
@Judy Thanks for stopping by. I hope your team enjoys the book and the activity.
@Niki Thanks for commenting. Cuisenaire rods! That’s a great idea. I used them that same day in another classroom to explore fractions. A future blog post, I hope. Also, I forgot to mention in this post that some students were given the challenge of working with a larger number (18).