Grade
2

Guess My Rule: Representation Rules

A red circle and a blue circle overlap. In the red circle: The expression 100 + 10 + 5. The number 199. The words one hundred seventy-eight. 1 hundred, 4 tens, and 7 ones. 4 double 10-frames, each filled with blue and red dots. And a dollar bill with 2 quarters and a dime. In the blue circle: The expression 500 + 80 + 9. The number 305. The words two hundred two. 2 hundreds, 3 tens, and 4 ones. And a dollar bill with 4 quarters and a penny. Where the circles overlap: The expression 100 + 85 + 15. The words two hundred. 1 hundred, 9 tens, and 10 ones. And a hundred mat with 10 ten-strips.
  1. What is the rule to decide what belongs in the red circle? What is the rule to decide what belongs in the blue circle? What is the rule to be in both circles?
  2. Can you draw or record a quantity or number that would go inside the intersection of the circles? How do you know?
  3. Draw a quantity or number that belongs in only the red circle.
  4. Draw a quantity or number that belongs in only the blue circle.

What do you notice about the quantities or numbers shown?

  • Make your own rule that uses quantities or numbers. You can use the circles below or draw your own.
  • If possible, show some examples that belong inside each circle and some examples that don’t belong in either circle.
outlines of overlapping red and blue circles, with space to write the rule for each circle
Printable Version

Google doc for printing and copying

Reference for Educators

Sample problems and solutions