Hello, 1st grader! Today we are going to learn about something called “plane symmetry” and how to find it in 3D shapes like cubes.

First, let’s talk about what “symmetry” means. When we say something is “symmetrical,” it means that it has two halves that are exactly the same when you fold it in half. For example, your face is symmetrical because if you draw a line down the middle, both sides will look the same.

Now, when we talk about “plane symmetry,” we’re looking at 3D shapes like cubes and trying to find a plane (which is like a flat surface) that divides the cube into two halves that are mirror images of each other. This means that if you were to hold up a mirror to one side of the cube, it would look exactly the same as the other side.

To help us understand this concept better, we have a worksheet here that asks us to draw all the planes of symmetry for a cube. This means we need to draw lines on the cube that divide it into two halves that are mirror images of each other.

So, let’s look at our cube. It has six faces, and we need to draw lines on it to find planes of symmetry. Let’s start by drawing a line that goes through the middle of two opposite faces, like this:

(insert image of line going through the middle of two opposite faces)

If we fold the cube along this line, we can see that the two halves are mirror images of each other. This means we’ve found one plane of symmetry!

Now, let’s try to find more. We could draw a line that goes through the middle of two other opposite faces, like this:

(insert image of line going through the middle of two other opposite faces)

Again, if we fold the cube along this line, we can see that the two halves are mirror images of each other. So we’ve found another plane of symmetry!

We could keep drawing lines like this until we’ve found all the possible planes of symmetry for the cube. Can you try to find another one? Look at the cube and see if you can draw a line that divides it into two halves that are mirror images of each other.

Remember, when we find a plane of symmetry in a 3D shape like a cube, it means that the shape has a special kind of symmetry that makes it look the same on both sides. This is an important concept to understand when we start studying more complex shapes and patterns.

## Printable 3D Shapes Symmetry Worksheets

**Answer Key**