Volleyball Machine Challenge for Grades 3-5

Background Information for Teachers

This section contains a quick review for teachers of the science and concepts covered in this lesson.

In this lesson, your students will use readily available craft/office supplies to build two devices that can launch a ball back and forth over a net, similar to the game of volleyball (although in this case, the devices are allowed to catch the ball). The 2019 Engineering Challenge had specific rules and limits on what materials students could use. You can choose to follow the same rules, or just use this lesson as an inspiration. If you have not already, watch this video for an introduction to the challenge.

Optionally, you could link this challenge to other science or engineering topics in your classroom. There is more information about these topics in the Additional Background section.

• Simple machines: use the project to learn about simple machines like the lever and the inclined plane. How can simple machines be combined to form a more complex machine that can launch a ball?
• Engineering design: you can use this project to walk your students through the engineering design process. They probably will not build a perfect machine on their first try. Instead, they will need to iteratively test and redesign their launcher/receiver in order to improve the design.

Additional Background Links

• Simple Machines: Facts, Science Trek
• Engineering Design Process, Science Buddies
• Build a Catapult, Scientific American

Prep Work (10 minutes)

• Gather all the materials you will need.
• Print the student worksheets if you will be using them.
• Optional: assign the introductory video for your students to watch before class.
• Optional: build at least one working ball launcher or catapult-style device to show your class. This may be useful if students have trouble coming up with their own ideas or understanding how to build a working launcher. You can get general ideas from the introductory video, and specific instructions for one type of catapult in this activity.
• Build "nets" for the students. The net dimensions are shown in Figure 1.
  • Tape two letter-size (8.5×11" or 21.6×28 cm) pieces of paper together along the 11" edge, overlapping by 1/2" (1.25 cm).
  • Fold the resulting larger piece of paper in half width-wise, so it is 16" (40.6 cm) long and 5.5" (14 cm) tall.
  • Prop the paper up to form an upside-down "V" shape. The bottom edges of the paper should be 2" (5 cm) apart. Tape the net down to a work surface like a table or the floor.

Engage (5 minutes)

Introduce the challenge to your students. Explain that their main goal is to build two devices that can launch a ball back and forth over a net, like in a game of volleyball. However, there are rules they have to follow, and they are only allowed to use certain materials. First, show your students the introductory video:

Then, go over the student worksheet (rules also included below).

Explore (90 minutes)

1. Design: Before they start building anything, have your students draw some of their ideas. Remind them to think about the materials they are allowed to use. They can label these materials on their drawing. That will help them show to build it.
2. Build: Younger students may have difficult building working designs independently. Guide the students through this process.
   1. Each group should discuss what they drew and decide what they will build. They can pick one person's design, or combine their ideas into a new design.
   2. After deciding, they should focus on building a single machine that is capable of launching the ball over the net. If your students get stuck, you can guide them toward a design you know should work (see Teacher Prep section).
   3. Test the machine and look for problems. Does anything break? Does the ball go high enough and far enough to go over the net? What can they change or fix?
   4. After getting one machine working, they can start building their second machine for the other side of the net. This machine needs to be able to "catch" the ball as shown in the video, and then launch it back over the net.
   5. After they have both machines built, practice launching the ball over the net and catching it.
   6. Now modify/add to the first machine so it can also catch the ball. This will allow them to launch the ball back and forth over the net.
3. Test: Now they are ready to test both machines. One student can operate the machine on each side of the net, as they try to launch the ball back and forth. They will need to make observations as they launch the ball. Does the ball get stuck? Does it hit the ground? Does it fail to go over the net? What causes these things to happen?
4. Iterate: emphasize that it is OK if their machines did not work on the first try! This is why real engineers test things, so they can fix them and make improvements. Encourage your students to keep making observations and improving their machines. Can anyone get the ball to go back and forth over the net two times? Three times? Even more? Now they are ready to do an official test for a high score!

Reflect (30 minutes)

Once students have finished building their devices, have a class-wide competition to calculate official scores.

1. Set up a single official net for testing.
2. One at a time, let each team bring their two devices to the official net and set them up. One student can operate each device.
3. Let the students place the ping pong ball in one of their devices.
4. Start the stopwatch and let the students start launching the ball over the net. Count how many times the ball goes over the net. Remember that students must wait for the ball to come to rest after each time they launch it. They are not allowed to touch or manually relocate the ball.
5. Keep going until the ball touches the ground or five minutes is up, whichever comes first.
6. Write down the number of times the ball went over the net for that group. They will need this information to calculate their score.
7. Move on to the next group.
8. If time allows, you can let each group go more than once to try and get a better score.

Discuss the results of the competition as a class.

• Did anyone draw designs that looked the same at first?
• Did anyone draw a design that no one else thought of?
• What problems did groups encounter during the building/testing process?
• Do the best designs have anything in common?

Assess

• Collect your students' worksheets and use them to assess how they worked through the design process.
• Ask each group to tell the rest of their class about their design. How does it work? Did they have any problems?

Lesson Plan Variations

Did your students enjoy this type of hands-on project? Check out the other Engineering Challenges and try them in your classroom!