### Overview

The class will play a game together to create a large design of a Mars rover made from geometric shapes, or tangrams. When the rover is complete, students will color and cut out their own set of tangrams and make their own Mars rover.

### Management

• Before doing the lesson, prepare the materials:

1. Using a computer projector, project the tangram rover pattern with interior lines onto the wall and hang the vinyl tablecloth so the projection appears on it. Adjust the size of the projection to fit the tablecloth.
2. Trace all the exterior lines using the permanent marker. Trace interior lines depending on the skill level of the students. Remove the tablecloth.
3. Place construction paper on the projection and trace the shapes onto the construction paper. Cut out the shapes. Make one extra of each of the shapes. Laminate, if possible.
4. Create a tangram die from the box by securely taping the box closed using the packing tape. Then, tape or glue the extra shapes you cut out, one onto each face of the tangram die.
• Locate an open space inside or outside the classroom for the game portion of this lesson. A circular area approximately 20 feet in diameter works well. If this amount of room is not available, make a smaller die.

### Background

We use rovers to explore the surfaces of planets and moons. As of 2022, NASA has sent five rovers to Mars and two are still operating on the surface of the Red Planet. Astronauts on the Moon used rovers to explore the surface, too.

Click and drag on this interactive image of the Perseverance Mars rover to take a closer look at its body, wheels, and more. Image credit: NASA/JPL-Caltech | › Learn more

The shape of a rover determines how it will fit into a rocket on its trip through space and what kind of surfaces it can explore once it arrives.

Many shapes that make up a rover are identifiable to young students in both two and three dimensions. Wheels are circular and different parts of the rover body are square or rectangular.

### Procedures

#### Review shapes

1. Review shape names using the enlarged tangram pieces. Encourage students to notice that these shapes are “flat” and lie in two dimensions (as opposed to solids in three dimensions).
2. As a class, note the colors of the tangram pieces and count the number of squares, triangles, and rectangles.
3. Ask students what shapes are not included. There are no circles, diamonds, trapezoids, hexagons, or ellipses.
4. As a class, note that the triangles are not all the same. Have students describe differences among the triangle tangram pieces. Encourage them to describe overall shapes and sizes in addition to color differences.

#### Build background and prepare to play

This artist's rendering depicts NASA's Perseverance Mars rover with its robotic arm extended. Image credit: NASA/JPL-Caltech | › Full image and caption

1. Show students pictures of Mars rovers. Look at different shapes that comprise the rovers.
2. Show students the large tangram rover outline on the vinyl tablecloth and demonstrate how the large tangram pieces fit the various outlines.
3. Show students the die and explain that the class is going to play a game to create a rover design from tangrams.

#### Create the rover design

Student teachers roll the tangram die as part of the Tangram Rocket lesson, which follows a similar format as this lesson. Image credit: NASA/JPL-Caltech | + Expand image

1. Place the vinyl tablecloth on the floor and have students gather around at a distance, making a large circle around the rover.
2. Spread out the large tangram pieces on the floor so that all of them are visible.
3. Demonstrate how to gently roll the die across the floor. Have students say what shape is “up” on the die.
4. Have a student select the matching tangram piece and place it on the vinyl tablecloth in the correct spot. To take the pressure off the student volunteer, have other students direct the volunteer toward the correct piece and spot on the vinyl tablecloth.
5. Now have a student roll the die.
6. Repeat rolling, shape identification, and placement as a class until all the tangram shapes are placed and the rover is built.
7. For more advanced students, use a tangram rover outline without interior lines and play the game again.

#### Exploration

1. Have students return to their desks. Give each student a copy of the tangram pieces and an envelope.
2. Instruct them to color the shapes as they please (or as instructed by the teacher). Have younger students color all the squares one color, the rectangles another color and the sets of identical triangles other colors. Provide examples of this on the board using the large tangram pieces.
3. Instruct students to cut out their colored tangram pieces and place them in the envelope.
4. Once all the pieces are cut out, have students recycle their trash and practice making their own tangram rovers with either the rover diagram with interior lines, the rover diagram without interior lines or no diagram at all (free-form creation).
5. Image credit: NASA/JPL-Caltech | + Expand image

### Discussion

• How did the rover on the play board compare to your free-form rover?
• What features did your rover have in one version versus the other?
• How many squares, rectangles, triangles and circles did you use in your free-form design?

### Assessment

• Ask students to point to a specific shape and evaluate it for shape recognition.
• Evaluate students’ ability to orient shapes to fit on the tangram rover.
• Evaluate students’ ability to color shapes.
• Evaluate students’ ability to use scissors to cut out shapes.

### Extensions

• Have students use their tangram pieces to create something besides a rover. If they need prompting, ask them to create a car, human, dog, etc.
• Have students take their tangrams home and encourage family members to work together to build a rover. Have students trace the family creation and bring it back to class to share.
• Introduce or review the concept of symmetry. Ask students to determine if the tangram rovers have symmetry. Look at individual shapes on the rover. Decide if they are symmetrical. Look closely at the triangles. Only one is symmetrical. In looking for symmetry in squares and rectangles, encourage students to think of different ways to divide these shapes in half. Find objects in the room that are symmetrical.
• Read a book as a class about building rovers. Examples include “Red Rover” by Richard Ho and Katherine Roy, “Rover Throws a Party” by Kristin L. Gray and Scott Magoon, and “Mars’ First Friends: Come on Over, Rovers!” by Susanna Leonard Hill and Elisa Paganelli. Ask students to identify the shapes used to build the rovers in the books. Compare these shapes to tangram shapes.
• Ask students what two-dimensional shape is most related to the die. Help them see the relationship between the two-dimensional square and the three-dimensional cube (equal sides).