Solve a Mirror Maze Challenge with the Law of Reflection

Overview

When light interacts with an object, it can be absorbed, transmitted, or reflected. This lesson focuses on materials that reflect light. Specifically, students will use mirrors and flashlights to investigate how light is reflected from a surface. By doing that, they will discover that when a light ray hits a reflective surface, its angle of incidence is equal to the angle of reflection, which is stated by the law of reflection. Students will then use their gained knowledge in a mirror maze challenge where they have to find a way to guide a light beam through a maze in order to hit a specific target.

Remote Learning: This lesson plan can be conducted remotely. The Engage section of the lesson can be done over a video call, then students can work individually and independently during the Explore sections, using the student worksheet and the maze template as guide. A set of materials can be prepared in advance or students can use materials found around the house. For example, old CDs can work as mirror replacements. The Reflect sections can be done over another video call. Students can show their final design solution either on the call or they can share pictures or drawings of their designs on a class drive.

NGSS Alignment

This lesson helps students prepare for these Next Generation Science Standards Performance Expectations:

• MS-PS4-2. Develop and use a model to describe that waves are reflected, absorbed, or transmitted through various materials.
• MS-ETS1-4. Develop a model to generate data for the iterative testing and modification of a proposed object, tool, or process such that an optimal design can be achieved.

This lesson focuses on these aspects of NGSS Three Dimensional Learning:

Science & Engineering Practices	Disciplinary Core Ideas	Crosscutting Concepts
Planning and Carrying out Investigations. Conduct an investigation and/or evaluate and/or revise the experimental design to produce data to serve as the basis for evidence that meet the goals of the investigation. Constructing Explanations and Designing Solutions. Construct a scientific explanation based on valid and reliable evidence obtained from sources (including the students' own experiments) and the assumption that theories and laws that describe the natural world operate today as they did in the past and will continue to do so in the future. Undertake a design project, engaging in the design cycle, to construct and/or implement a solution that meets specific design criteria and constraints Apply scientific ideas or principles to design, construct, and/or test a design of an object, tool, process or system Engaging in Argument from Evidence. Evaluate competing design solutions based on jointly developed and agreed-upon design criteria.	PS4.B: Electromagnetic Radiation. When light shines on an object, it is reflected, absorbed, or transmitted through the object, depending on the object's material and the frequency (color) of the light. 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. Sometimes parts of different solutions can be combined to create a solution that is better than any of its predecessors. 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.	Patterns. Patterns can be used to identify cause and effect relationships. Cause and Effect: Mechanism and Prediction. Cause and effect relationships may be used to predict phenomena in natural or designed systems.

Materials

Per Student Group of 2–3:

• One flashlight with a narrow beam
• 3 small mirror squares (4" x 4")
• 3 squares of aluminum foil (4" x 4")
• 3 pieces of string (about 5" long)
• Colored construction paper (1 sheet)
• 12 clothespins or binder clips
• Masking tape or painter's tape
• Protractor
• Ruler
• Yardstick
• Black cardstock paper (7 sheets)
• One printed maze template
• One printed and cut target from the target template

For Teacher:

• Scissors
• Ruler
• Small mirror square (4" x 4")
• Flashlight with a narrow beam
• Construction paper (1 sheet)
• Piece of string (about 5 inches long)