Splash (@SplashSpeaks) / X

Aug 2, 2022

Dad: What shape will the area model be for the multiplication problem 12 x 12? Me: ...a square. Dad: (makes the model in an app) What's one way you could break apart this area model to help you find the product of 12 x 12? Me: ...I could cut it in half? Dad: Let's see!

Dad: This is another example of the idea we've been talking about with geometry. We can start with something simple and create something more complex. What simple thing is our complex design made of? Me: Short lines. Dad: Yeah, we made this by drawing short lines over and over.

Girl sitting at a table. She is using a ruler to draw short lines on a piece of paper. The design will become four rows of four squares. Currently she is drawing the third side on each soon-to-be square.

Girl sitting at a table using a ruler to draw lines on a piece of paper. The current phase of her design shows four rows of four squares.

A piece of paper showing a geometric design that is composed of four rows of four squares with three rows of three star-shaped octagons embedded between the squares.

Me: (writes B next to 39 x 48) Dad: Hmm, only one of those can be B. Which one do you think it is? Me: (erases the B on 39 x 48 and 12 x 39, silently thinks for a while, then writes B next to 39 x 48 and A next to 12 x 39) Dad: Let's make these models and see!

Child sitting on the floor in front of a small white board, marker in hand. On the white board is a column of multiplication expressions with letters written next to them.
12 x 39 B
39 x 39 E
39 x 33 D
39 x 11 C
39 x 48
The marker is hovering over this last expression.
Next to whiteboard is a sheet of paper with five rectangles each labeled with a letter A to E.
A is long and skinny
B is long and wide
C is tall and skinny
D is tall and wide
E is square

Dad: Do you want the square or pentagon? Me: Square. (after drawing for a bit) Me: You have to draw a lot more lines. Dad: Why do you say that? Me: Because you have more sides. Dad: I wonder how many squares and pentagons we'll draw in all.

Two hands on a piece of paper. One hand is holding a pencil and the other is pressing on a ruler. The picture being drawn is of a square with increasingly smaller squares inscribed within in a nesting pattern. Nearby is another sheet of paper showing a similar drawing in progress using a Pentagon instead of a square.

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