Motley Crab Adder is a math character who depicts addition as just combining where the quantities being combined are not necessarily equal. Use the story and follow-up below to tell about the jobs she does. Emphasize that addition is about combining things and that “just combining” means that the numbers for the things may be equal (like 4+4) or not (like 3+5). Have elementary school students mime the combining actions implicit in the jobs in the follow-up to acquire a literal feel for addition as just combining.

Motley Crab Adder is a combiner. She just combines things, like toys that need to be picked up and put away. When she does, she doesn’t worry if the numbers that go with the things she combines are the same. She just combines the things. If asked why she does that, she says “That is my job.” If asked how long she has had that job, she says “Always.” If asked if she likes her job, she says “Yep.” If asked if she will ever get another job, she says “Nope.” So Motley’s friends are very careful not to drop anything around her. They know if they do that she will just combine it with everything else she is combining. Do you know anyone like Motley Crab Adder? Are you ever like her? Explain.

• Making a sandwich, putting a puzzle together, and picking up dirty clothes are Motley Crab Adder jobs around the house. Show me (mime) what it looks like to do those jobs. What are some other Motley Crab Adder jobs around the house? Show me (mime) what it looks like to do those jobs.

• Hanging coats in a closet, putting pencils in a box, and writing a story are Motley Crab Adder jobs at school. (In writing a story, one is combining words and just combining them because the number of letters in the words aren’t necessarily the same for every word.) Show me (mime) what it looks like to do those jobs. What are some other Motley Crab Adder jobs at school? Show me (mime) what it looks like to do those jobs.

• What are some other ways to say (or imply) “just” combine? Make a list of these words and post it where it can be seen and extended. In addition to the usual keywords for addition, like “all together,” include words like add, assemble, assimilate, bond, bunch, cluster, collect, compile, connect, fuse, gather, group, integrate, join, link, mass, meld, merge, mix, pool, together, and unite. These words transcend the contrived language in arithmetic word problems and heighten students’ awareness of the many everyday occurrences of addition in and out of school.

• Optional: Write and illustrate a story about Motley Crab Adder.

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