The blocks I am going to use now are quite special. Each edge is one centimeter long, so this means each block is one cubic centimeter, which is a standard unit that we use to measure how much space an object occupies, or the volume of an object. We need a standard unit because a standard unit is one size, and it enables us to accurately find the volume of objects and construct objects that have the same volume as each other.

Now I’ll build two towers using the cubic centimeter blocks. Each tower will have a base of four blocks. Now we can put another layer on top of each tower, four for this tower and four for that one. There are still some blocks left, so we’ll put another layer on each tower. Look at the towers. Do they look the same to you? They look the same to me. Let’s check. There are four blocks on the bottom layer, four on the next, and four on the top of this tower. So this first tower has 12 blocks. And the second tower also has 4 blocks on each of its layers, so, we’ve used 12 in this tower also.

We’ve used 12 cubes to build each of our towers, and because the cubes are a standard size, we know both towers take up the same amount of space. Can you remember what was special about the blocks I have just used? Yes, each of their sides measures one centimeter and their volume is one centimeter cubed.

If we know each block is 1 cubic centimeter and each tower has 12 blocks, what do you think the volume of each tower is? We can say that each of our towers has a volume of 12 cubic centimeters, because each block in the tower is 1 cubic centimeter.