View examples of student solutions by clicking on a level below:

Can You Make Light Change Direction?

In groups of two, you will explore and investigate the materials available to find ways to make light change direction. First, place the target at least 3 feet away. Then, use your flashlight to shine light into the mirrors to see if you can change the direction of the light so that it reaches your target.

The light cannot travel directly to the target. It must hit at least 2 mirrors first. Try different angles for the flashlight. Try moving the mirrors to different positions. As you observe and investigate, record your observations. Draw a picture of what you did and what you observed. Use labels for your picture and then write about these observations. What did you learn about the direction of light? What new questions do you have?

Grade Level

K - 2

Big Ideas and Unifying Concepts

Cause - Effect

Physical Science Concepts

Properties of Matter
Transfer and Transformation of Energy

Design Technology Concept

Use of Tools

Time Required for Task

Approximately one 45-minute session

Context

This task was developed as a means to provide the teacher with ongoing assessment information about how well the students draw and write about their observations and how well they explain what they are learning. These are skills that students have been working on most of the year through this light unit, as well as other units. Prior to this investigation, students had spent time observing and investigating light and how light behaves. As part of this unit, students will also explore the connections between light and color. (See also K-2 inquiry task in this issue: Can you make a rainbow of light?)

What the Task Accomplishes

This task is used mainly for ongoing assessment purposes. It can also be used as an instructional task. It is a means to find out what ideas the students understand about light and how light behaves and how well they can record their observations. Specifically, it assesses their ability to observe, record through writing and drawing, and communicate their observations and learning.

How the Student Will Investigate

We began first by having a whole group discussion to review some of the things the students knew about light already. We reviewed that the students knew that light traveled in a straight line. Then, we discussed the challenge: Can you make light change direction so that it will hit a target? The teacher showed the students how she could shine the flashlight right at the target and told the students that they had to use mirrors, at least 2, to change the direction of the light so that it did not travel directly to the target.

We reviewed recording skills and asked students to make sure they recorded their observations and things they tried and to discuss what they learned from their investigations. Then the students worked in groups of two, made targets, and used the materials to create paths for the light to travel so that it would reach its target. As students investigated, they recorded their observations using words and pictures. Once students were finished observing, they could record new questions at the bottom of their sheet that we could investigate later. As a whole group, we discussed some of their observations and questions and added these to our lists.

Interdisciplinary Links and Extensions

Science

During this unit, students conducted a number of guided investigations related to concepts of light energy. Students investigated how light travels in a straight line, how to "bend" light, and shadows and colors. At the end of the unit, students will raise their own questions about light to plan and conduct investigations to find out the answers. Each student will then present his/her investigation to the rest of the class.

Students can also learn about the human eye and how it works.

Language Arts

Whenever possible, it is important to connect science to literacy. Reading non-fiction books about light helps students deepen their understanding of concepts and helps them learn to read for information. Having fiction books available for students to read helps them make connections between science concepts, things that happen in the world around us, and the role science plays in our lives. Here is a brief list of some children's literature that relates to the concept of light:

Fireflies in the Night, by Judy Hawes
Keep the Lights Burning, Abbie, by Peter and Connie Roop
Color: From Rainbows to Lasers, by Franklyn Branley
Making Light Work: The Science of Optics, by David Darling
Light and Dark, by Terry Jennings
The Laser Book, by Clifford Laurence
Color and Light, by Barbara Taylor

Teaching Tips and Guiding Questions

The excitement level can be very high during an exploration of new materials. We often use the strategy of "stop, drop, and write" during these explorations to make it easier for students to focus on the communication of learning. Two or three times during the exploration, we call for students to freeze, then to put down their materials, and write for a few minutes (at least 5) about their observations so far. This way they don't leave all the recording until the end, when frequently they may have forgotten some of the things they did and observed.

Some possible guiding questions to ask students before, during and after they investigate include:

How will you "line up" the mirrors? Does the light reach the target?
What is the light doing? How can you change the direction of the light?
What happens when you move one of the mirrors? Two of the mirrors? Does it matter where the mirrors are pointing?
What happens if you change the position of the flashlight? What if you move the beam of it up? Down?
Does the light shine as brightly as when it goes in a straight line to the target? How could you find out?
How can you record your observation? What words will help you describe what you learned? What should you label in your drawing?
What new questions do you have?
Did anything surprise you?

Concepts to be Assessed

(Unifying concepts (big ideas) and science concepts to be assessed using the Science Exemplars Rubric under the criterion: Science Concepts and Related Content.)

Observing and explaining cause-effect relationships, with some justification, using data and prior knowledge. (Cause-Effect)
Physical Science: Transfer and Transformation of Energy - Energy is a property of many substances and is transferred in many ways. Light is a form of energy that travels through space. We see only visible white light. Light travels in a straight line from the source until it strikes an object; light can be reflected or absorbed by objects it strikes. Objects can be seen because of the light they reflect.
Physical Science: Observing physical properties and characteristics - By observing patterns of how light behaves, students can begin to make predictions and classify materials; and understand the effects of changes, such as decreasing and increasing intensity.
Design Technology: Tools are invented to extend the ability of people (to make things, to move things, to shape materials, to see things more clearly).

Skills to be Developed

(Specific science process skills assessed using the Science Exemplars Rubric under the criteria: Scientific Procedures and Reasoning Strategies and Scientific Communication/Using Data.)

Predicting/Hypothesizing, Observing, Manipulating tools and materials, Collecting and recording data, Generating new questions to test, and Challenging misconceptions.

Links to Science (and other) Standards

Scientific Method: Students describe, predict, investigate, and explain phenomena.
Scientific Theory: Students look for evidence that explains why things happen, and modify explanations when new observations are made.
Physical Science - Properties of Matter: Students describe and sort objects and materials according to observations of similarities and differences of physical properties. Students observe and describe physical properties of light.
Physical Science - Transfer and Transformation of Energy: Energy is a property of many substances and is associated with heat, light, electricity, mechanical motion, sound, nuclei, and the nature of a chemical. Students observe that light is a form of energy and can be reflected or absorbed by objects it strikes.
Communication: Students use verbal and nonverbal skills to express themselves effectively.

Suggested Materials

For this task the teacher will need to provide a recording sheet for each individual student.

Also provide:

Flashlights, all different sizes - Have some extra batteries and bulbs on hand as well. (We also asked each student to bring in a flashlight from home. Remind them to carry it safely, as dropping it can damage the filament in the bulb.)
Construction paper and white paper
Crayons, markers
Mirrors (either flat rectangular mirrors with clay to hold them up, or use vanity mirrors with stands, from your local dollar store)

Possible Solutions

In this task, students are asked to record their observations using pictures and words and to discuss what was learned. These observations should be detailed and descriptive. Written observations should use appropriate vocabulary based upon prior knowledge and indicate what students already know, as well as what they learned from this exploration. New questions should be included when appropriate.

Task Specific Rubric/Benchmark Descriptors Click on a level for student example.
Novice	The student included a drawing of what was tried. There are labels, but they only indicate how the materials were set up, not how the light traveled. The student included only one observation: that the set-up worked. The student only used one mirror to change the direction of the light and hit the target.No new questions were raised.
Apprentice	The student included a drawing of what was tried. There are labels to indicate how the materials were set up to change the direction of the light. The student shows the light going from the flashlight to the mirror, but not how the light traveled to reach the target. The student made one observation about what happened but includes no details about how the light got to the target. The student only used one mirror to change the direction of the light and hit the target. A question was raised that directly relates to the investigation.
Practitioner	The student included a drawing of what was tried. There are labels to indicate how the materials were set up to change the direction of the light and how the light reflected off of the mirrors to reach the target. The student included one observation about what happened. Appropriate vocabulary is used to describe his/her observation (light bounces off a mirror). The student used two mirrors to change the direction of the light and hit the target. A new question was raised that relates to the observations in the investigation.
Expert	The student included a drawing of what was tried. There are labels to indicate how the materials were set up to change the direction of the light and how the light on the mirrors traveled to reach the target. The student included two observations about what happened. Appropriate vocabulary is used to describe his/her observation (light bounces, light reflects off the shiny mirror). The student used two mirrors to change the direction of the light and hit the target. Two new questions are raised that relate to the observations in the investigation. One question extends thinking to trying to bounce light off of other objects.

Author

Tracy Lavallee has been a third grade teacher for 12 years. She spent the last two years working as a science and math consultant for the Vermont Institute of Science, Math and Technology and is currently the K-5 Science Coordinator for the South Burlington School District, in Vermont.