# Sept 12, 2020 – Block Multiplication

My eldest child is logical and loves order. Math came easy for him. He likes to line things up. He likes the facts of math.

2 + 2 = 4.

No other answer, nothing to be philosophical about. Just black and white.

Then God gave me my second. He loves color and movement and pictures and shapes and textures.

2 + 2 = 4 wasn’t simple for him. He needed to visualize it. The first thing he would ask is “Two what?”

Math became a whole new challenge to me as a homeschooling mom. We had to think outside of the box.

Multiplication tables, so easy for my first to memorize and spit back out, became a new challenge for my second.

We had games and songs and Times Tales and skip counting on the swing (movement helps so much!).

When we got to double digit numbers, multiplication turned nightmarish.

He couldn’t keep the numbers lined up. We switched to graph paper. It helped but wasn’t the golden ticket.

I spoke with the Gifted teacher at our local school. She was an angel. She introduced us to block multiplication.

We went from meltdowns over multiplication to being able to do any problem given. Of course we added color which makes everything better for a visual learner.

I’ll post a video as well, but I’d like to walk you through the steps here as well.

First, you need graph paper. It makes math so much easier. Everything stays lined up and orderly, preventing many mistakes.

Let’s do this problem: 345 x 628.

Now in the traditional way of multiplication, there’s a lot of moving and keeping things lined up. In block multiplication, it becomes a game similar to Battleship. Remember that game? It’s a grid.

We will draw a grid for this problem:

I will use 4 small grid squares for each number. This problem has a 3 digit number times a 3 digit number, so we need our blocks to match.

Now we will split them diagonally.

I know this may seem like a lot of work, but for your visual kiddos, once they learn it, it’s way faster than a meltdown with every problem.

Now we add color. I prefer color pencils so that the pencil still shows up. Markers are too dark, although highlighters work well. Crayons make a waxy coating.

Now we multiply. Simply using the “battleship” grid pattern. You will only have two digits for each fact. The ten goes in the upper half of the box, and the one goes in the lower half.

5×6=30, 5×2=10, 5×8=40

Move to the next column.

4×6=24, 4×2=8 (notice the zero in the ten place holder), 4×8=32

Last column.

3×6=18, 3×2=06, 3×8=24

We will now add, starting at the bottom right and moving to the top left, diagonally. In this case, red, yellow, green, orange, blue, lime green.

The zero comes down. Then 0+4+2=6.

Then 0+1+8+3+4=16. The 6 goes in the green, and the ten carries over to the orange. We keep going.

I circled the carried ones so that we know they need to be added and are not part of the answer.