Let’s learn how to multiply with Lego.

This construction game has many applications in learning mathematics, as we saw a while ago when I proposed using Lego to work on weight in a manipulative way.

By doing this activity you will see that it allows you to work on a geometric model for multiplication, something very important both for understanding the operation and for delving into numerical sense.

## We build candy boxes to multiply with Lego

I found the activity I found on the Frugal Fun4Boys blog interesting to use both at home and in the classroom, as well as fun for children.

It involves building boxes to store candy with Lego pieces.

### Materials

- 1 x 1 Lego pieces in assorted colors
- 1 x another dimension Lego pieces in a single color (in the photographs you can see that they chose white).

The proposal is **to build boxes to store 8, 15, 24 and 30 sweets** . You tell the children that the boxes have to be shaped like rectangles and squares but they can design the dimensions.

### A box to store 8 sweets

In the photograph we see how, faced with the proposal to save eight sweets, the student chose to build a rectangle with a base 4 and height 2, that is, 4 x 2. He then made a drawing that represented said rectangle.

### Even more difficult

As we propose numbers that are the result of multiplying larger factors, the difficulty becomes greater.

We can also encourage boys and girls to make different boxes for a certain amount of sweets, that is, think about different factorial decompositions of the same number.

Look how they have built two different boxes for 24 sweets:

### Extensions

#### With power strips :

One of the best applications of using power strips is that children can visualize the concepts (this activity is included in the course ” Working with power strips “).

#### With polycubes :

Polycubes can also be used. As with Lego pieces, you choose one color for the box and the rest of the colors are the candy.

#### Reverse action:

When they have already built many boxes and have drawn them on grid paper, it is time to propose the reverse action: they are given the number of “candy” or 1×1 pieces in varied colors and a dimension or side of the box. so that they find the other.

With this activity we will be introducing division as the inverse operation of multiplication.

#### Find squares:

Can we build square boxes? Thanks to the manipulation of the pieces and the research, they will be able to conclude that only certain quantities of sweets (4, 9, 16, 25,…) can be stored in square boxes. Great discovery of square numbers!

This activity has many applications to deepen the understanding of multiplication, to begin division and also to develop number sense.