Grade 1

Share the Headline Story with the class. You might encourage children to suggest numbers that you could be thinking of, and also to rule out numbers that you could *not* be thinking of.

This Headline Story is a connection to language. The distinction between 12 and 13 —that 13 is teen number, and 12 is not—is not important from the point of view of the base-ten structure. However, this story suggests taking a closer look at the names of some numbers.

I’m thinking of a number. If you add ten to my number, the answer is in “teen.”

- My number could 7, so the answer would be 17.
- My answer could be 13, 14, 15, 16, 17, 18, or 19.
- My number could not be 0, 1, or 2 or any number greater than 9.

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