It’s tempting as you reach the end of the school year to feel that you might be able to relax. I started to think that, especially considering how hard I hit arrays and those models back in our multiplication unit. Here I am thinking finding area would be a breeze for my students, but it isn’t.

Yet, having taught fourth and fifth grade, I know just how important this math standard is. I mentioned it as an essential MATH STANDARD in this blog also.

Why?

Because area is going to be the foundation on which fourth graders will build their understanding of multi-digit multiplication. In fifth grade, many students lean on the AREA model to support them in multiplying decimal numbers. We can’t skip this essential standard!

That’s why it is necessary that we make sure third graders understand how to find area with basic arrays, rectangles, and simplified rectilinear shapes. 

How to find area in third grade?

In third grade, students explore how much space is covered by a shape by using tiling. We ask them to practice covering rectangular shapes and start by counting the number of square units needed to cover it completely. 

As third grades get more familiar with what area is, we ask them to use the formula to find area, length x width. We use rectangular shapes that have side lengths using the basic math facts from 1 – 9.

We move to more complex rectilinear shapes that require third graders to divide these shapes into smaller rectangles. They still use the formula of length x width to find the area, but then they add the partial products to find the total area of the shape.

Finding area in fourth grade:

When fourth graders are introduced to mult-digit multiplication, they commonly use the area model. This allows them to break apart larger numbers into their place values. They use rectangles for each place value. This means that if they are multiplying 22 x 7, they will draw a rectangle that is divided into two pieces, one for the tens, and another for the ones. 

Then, fourth graders use their knowledge from third grade to multiply the length and width of the sides to find the total area. 

This is a bridge between the prior knowledge and experience gained in third grade, and allows students to step into more abstract methods (algebraic, distributive, and the traditional algorithm). 

Using decimals to find area in fifth grade:

In my experience, many fifth graders lean on the area model when decimal multiplication is introduced. 

Again, fifth graders use a rectangle divided according to place value. For example, if the problem was 2.6 x 7, there would be a place for the ones and another for the tenths.

My students shared that they felt the most confident using the area and place value sections models as they were the most comfortable with them. They had used them since third grade to multiply, so they understood them best. 

To wrap it up:

•  Area uses length and width to find how much space is covered by two dimensional figures.
• In third grade, students use length and width to find the area of rectangular shapes that have side lengths between 1 – 9.
• Fourth graders use their knowledge from third grade to create area models with two and three digit factors.
• Many fifth graders like using the area model when decimal multiplication is introduced.
• Skipping or failing to create a firm understanding of area sets fourth and fifth graders up for struggle as these strategies are used as multi-digit multiplication is introduced.