How many squares are missing?

How did you see it?

How could you figure it out?

3, 4, 5

Attending to and using structure

Equal means the same

Composing and decomposing number

Relating part and whole

Thinking in equal groups

Connecting area and multiplicative thinking

Composing and decomposing with shapes

After the class has discussed the questions above, you can extend this activity by posing the following questions:

If you have square tiles or blocks, build an array with some of the pieces missing.

How many pieces are missing?

How do you know?

Test your ideas by filling in the missing pieces and counting how many it took to complete the array.