Introduction

In this hands-on engineering challenge, students will explore the principles of energy transformation by designing and building their own working waterwheel. Using a limited set of materials, they will convert the potential energy of flowing water into mechanical energy capable of lifting weights, applying creativity, problem-solving, and teamwork along the way.

Materials Needed

Note: In the design process, students will create their own design and decide what specific materials they will need. The material quantities below can be provided to each group of students as a “materials pack” as they brainstorm. They will not use every piece but will decide what would go best with their design to reach the end goal.

• Student Handout
• 12-16 oz Plastic Cup (1-2)
• Plastic Spoons (5-6)
• Medicine cups (5-6)
• String (1-2 ft)
• Tape (1 roll)
• Scissors (1-2 pairs)
• Pencil/wooden skewer (for axis) (1)
• Plastic bottle lids (1-2)
• Pennies or equivalent weights (3)
• Water source (a sink or large container of water) (1)
• Stopwatch (1)
• Measuring cup (1)
• Flinn Scientific Kit (optional): Complete lab kit available here: Build a Water Wheel Kit

Students Will Be Able To

• Design and construct a functional waterwheel using provided materials to convert water power into mechanical motion.
• Test and measure the performance of their waterwheel, including the ability to lift a specified weight.
• Analyze and explain how energy is transformed from potential energy in water to mechanical energy in a rotating wheel.
• Evaluate their design for efficiency and suggest modifications to improve performance based on collected data.

Procedure

1. Introduction to Energy Transformation: Before starting the lab, use the pictures of waterwheels and energy transformation diagram (included below) to discuss the principles of energy transformation, focusing on how potential energy from water can be converted into mechanical (kinetic) energy to turn a turbine. Explain how waterwheels have historically been used to perform tasks like grinding grain and generating electricity.

2. Design Phase: Before building, introduce students to the design challenge, along with the Student Handout and material packs that they will have to work with. Divide students into groups and instruct them to brainstorm designs for a waterwheel that can lift at least three pennies (or equivalent weights).

Consider the size and shape of the paddles, the axis of rotation, and how the wheel will be supported. Using the Experimental Design Form in the Student Handout students can formulate the design question, sketch out their designs and clearly list the materials they think they will need to ensure successful construction in the Research section. Once students have completed the design phase, and formulated their Hypothesis (stating the task(s) they believe their specific design will be able to accomplish), they can begin constructing their waterwheel.

3. Construction Phase: Instructions for students who may be struggling with a design:

• Use plastic lids as the wheel base.
• Attach plastic spoons to the lid to act as paddles using tape or glue, ensuring they are evenly spaced.
• Create an axle using a pencil or dowel, securing it through the center of the lid.
• Attach one end of the string to the axle, and the other end to a small cup or medicine cup where pennies will be placed.

4. Testing Phase:

• Place the waterwheel in a sink or large container, ensuring it is aligned with the water flow.
• Gradually increase the water flow and observe the wheel’s motion.
• Measure the time it takes for the wheel to lift the pennies a certain height.
• Record observations and adjust the design as necessary for optimal performance.

5. Data Collection and Analysis: In the last section of the Experimental Design Form in the Student Handout, record the number of pennies lifted, the time taken, and any changes made to the design during testing.

Assessment

• Submit a lab report detailing the design process, observations, and conclusions. This can include a neat and clean version of the Experimental Design Form (Student Handout).
• Answer reflection questions thoroughly.
• Assessment Rubric

Student Examples: