Grade 1

Share the Headline Story with the class. If children need help getting started, pose questions such as, “What numbers could the triangle and sqaure stand for?” or “If the square stands for 10, then what does the triangle stand for?”

Mitch used shapes to write this number sentence.

- The triangle stands for one number and the square stands for another.
- If the square stands for 10, then the triangle stands for 8 because 10 + 8 = 18.
- If the square stands for 12, then the triangle stands for 6 because 12 + 6 = 18.
- If the square and the triangle both stand for the same number, then the number must be 9 because 9 + 9 = 18.
- The bigger the number we put in the square, the smaller the number that goes in the triangle.

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