Cricket Wicket Knockdown Challenge for Grades 6-8
This engineering challenge is based on an internal competition designed by employees at Fluor Corporation.
Teach your students about the engineering design process with this fun lesson plan. They will design and build a ball-launching machine to knock down a target. Optionally, they can enter their designs in the 2020 Engineering Challenge for a chance to win a cash prize for your school! Teachers, note that elementary school and high school versions of this lesson plan are also available.
- Design and build a ball-launching machine based on specified criteria
- Iteratively test and modify the machine to improve its performance
NGSS AlignmentThis lesson helps students prepare for these Next Generation Science Standards Performance Expectations:
- MS-ETS1-2. Evaluate competing design solutions using a systematic process to determine how well they meet the criteria and constraints of the problem.
- MS-ETS1-4. Develop a model to generate data for iterative testing and modification of a proposed object, tool, or process such that an optimal design can be achieved.
- MS-PS3-5. Construct, use, and present arguments to support the claim that when the kinetic energy of an object changes, energy is transferred to or from the object.
Science & Engineering Practices
Constructing Explanations and Designing Solutions. Undertake a design project, engaging in the design cycle, to construct and/or implement a solution that meets specific design criteria and constraints.
Optimize performance of a design by prioritizing criteria, making tradeoffs, testing, revising, and retesting.
Disciplinary Core Ideas
ETS1.B: Developing Possible Solutions. A solution needs to be tested, and then modified on the basis of the test results, in order to improve it.
There are systematic processes for evaluating solutions with respect to how well they meet the criteria and constraints of a problem.
ETS1.C: Optimizing the Design Solution. The iterative process of testing the most promising solutions and modifying what is proposed on the basis of the test results leads to greater refinement and ultimately to an optimal solution.
PS3.B: Conservation of Energy and Energy Transfer. When the motion energy of an object changes, there is inevitably some other change in energy at the same time.
Structure and Function. Structures can be designed to serve particular functions by taking into account properties of different materials, and how materials can be shaped and used.
Systems and System Models. Systems may interact with other systems; they may have sub-systems and be a part of larger complex systems.
If you want to enter your device in the 2020 Engineering Challenge, you can only use the materials listed below. Each item has a maximum allowable quantity and a point cost (each) that will be deducted from your score. Note that you can cut the materials, but costs are not prorated; e.g., if you cut a piece of paper in half and only use half of it, it still costs 10 points.
|Item||Maximum Quantity||Point cost (each)|
|Cardboard (max size 12"x12" or 30x30 cm)||1||10|
|2 oz paper or plastic cup||10||3|
|Wooden craft sticks (4 ½" or 11.5 cm)||10||1|
|Wooden pencils (circular or hexagonal cross-section, approx. 7–8" or 18–20 cm length)||10||1|
|Paper (printer/copier paper, not construction paper or cardstock; letter or A4 size)||10||1|
|Rubber bands (size 32, 3" long unstretched and 1/8" wide)||10||2|
|Cardboard tube (1 unit = 1 paper towel roll or 2 toilet paper rolls)||2 units||9 per unit|
|Roll of clear adhesive tape (Scotch® tape or equivalent, 1/2" or 3/4" width, max length 500")||1||10|
|Duct tape (up to 90 feet total, no more than 2" wide)||90 feet||20 (if any used)|
|Tools and Testing Materials (no point cost)|
|Ping pong ball||1|
|Ruler or measuring tape||1|
|2 oz paper or plastic cup||1||Used to build the wicket|
|Rubber or plastic eraser (approximately 2"x1"x1/2")||1|
|Modeling clay, Play Doh®, or homemade dough.||Enough to fill the 2 oz cup halfway|
Background Information for TeachersThis 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 and office supplies to build a device that will launch a ping pong ball at a target to try and knock it down (the target is called a wicket, inspired by the game of cricket). If you have not already, watch this video for an introduction to the challenge. If you want to enter your students' designs in the 2020 Engineering Challenge, make sure you review the official materials and rules before you begin.
This challenge allows you to explore some interesting topics in physics and engineering. Rather than explain these topics in detail, this background section will give you a brief overview of each one, and you can decide which, if any, to address with your students. 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?
- Projectile motion is a classic topic in physics classes. How do the initial velocity and launch angle of the ball affect its range? What trajectory (i.e. a high, steep trajectory or a low, shallow trajectory) makes it easier to catch the ball?
- Energy is another classic physics topic. The ball needs kinetic energy, the energy of motion, to fly through the air. Where will that energy come from? It could come from elastic potential energy, the energy stored in a stretched material, like a rubber band. It could come from gravitational potential energy, the energy stored in an object that is raised up off the ground. Or, the energy could come from work that you do with your hand by exerting a force.
- Conservation of momentum is yet another topic typically covered in physics classes. An object's momentum is equal to the product of its mass and its velocity. When two objects collide, their total momentum is conserved. Your students can examine what happens when the light, fast-moving ping pong ball collides with the heavy, stationary eraser.
- Engineering design: you can also 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.