iTEEM Lesson Plan
Name:
Teacher
Date: April 22, 2011
School: USD305
Grade Level: 6th Grade
Subject Area of your lesson: Science
Essential Question:
What would the world be like without color?
Summary: Students will demonstrate how light can be produced, reflected, and separated into
various colors.
Targeted Content Standards and Benchmarks:
2.4.3
Lesson timeline:
1 – 45 min class (provide two class periods if including differentiation activities)
Resources: (Please include links to websites, names of videos, or any other resources used.)
Teacher: shallow baking dish, water, small mirror, modeling clay, white paper, 3 flashlights, red,
green and blue cellophane
Iteem light lesson flipchart
Bill Nye: Light Optics Disney (on Montage) ch 1-6
Brainpop: Rainbows, Refraction, or Color – waves of energy
Student: clear plastic cup, water, straw, pencil, penny, prism, flashlight, white paper, science journal
http://micro.magnet.fsu.edu/primer/java/prism/index.html
http://www.msnucleus.org/membership/slideshows/light2.html
Activity Sheets
Background for Teachers:
The Law of Reflection states that when light hits a surface, it is always reflected at the same angle it strikes the
surface: the angle of incidence equals the angle of reflection. This is best demonstrated by throwing a ball at a
smooth surface. The angle at which it hits will equal the angle at which it bounces back (45° going in equals
45° going out). The angle at which you throw the ball is called the angle of incidence, and the angle at which
the ball bounces back is called the angle of reflection.
Light travels in straight lines, but it bends as it passes from one transparent medium to another at an angle.
This is called refraction. A good example of this is placing a pencil in a clear glass of water. The part of the
pencil above the water appears to be broken off from the part below the water. When the light travels at an
angle, one part of the light will reach the water before the other, so it slows a little before the other part slows.
People first thought rainbows were something of a supernatural explanation. The first person to realize that
light contained color was a man in 1666 named Sir Isaac Newton. Newton discovered the colors when he bent
light. We see a rainbow of colors when we use a prism or water to separate the colors of sunlight. Light is bent
as it passes through the water or prism and the colors are spread apart into a spectrum. Each color becomes
individually visible. Each color has a different wavelength with red being the longest and violet the shortest.
When light passes through a prism or water, each color is bent at a different angle.
iTEEM Lesson Plan
If you were asked to draw a rainbow, in which order would you put the colors? Young (and sometimes older)
children may think each rainbow, like each person is unique. They're not aware that real rainbows contain
specific colors and that these colors are always arranged in the same order. This is quite an amazing idea. All
the rainbows that ever were or ever will be have the same colors in the same order.
Authentic Connection Questions: How does content connect to the real world? Why do the
students NEED to learn this?
What makes a rainbow? How can a rainbow help us understand the colors in a picture? Can you imagine what
our world would be like if there were no color? Students need to understand that science affects the world
around us.
Invitation to Learn (focus activity):
Show students optical illusion images (on flipchart) – let them “ooh and awe” and then introduce the concept of
reflection.
Color is an essential part of our life. Everything we see has color. Colors are in the clothes we wear, in the
plants and animals. The sky is blue. The snow is white. The asphalt is black. Can you imagine what our world
would be like if there were no color?
Instructional Procedures: (Provide a description of the steps you will take to teach this lesson.)
Introduction:
1. Begin by briefly discussing rainbows. (see pg 11 flipchart)
o
How many of you have ever seen a rainbow?
o
Where were you when you saw the rainbows?
o
Can you explain what makes a rainbow?
2. Help students understand that the colors in rainbows actually come from white light.
3. Explain to the students that light bends and when we bend light we can see the colors of the rainbow. These
processes are called reflection and refraction.
Part 1: Making Light Bend
1. Give each student a clear plastic cup half-full of water and a straw. Instruct the students to put their straw
into a glass of water and then look at the straw from the side.
2. Ask them why the straw looks broken when it is not.
3. Explain that light rays change direction as they leave the water. This 'bending' of the light rays makes the
straws look bent in the middle, even though they are actually straight. This process is called refraction.
4. Take out the straw and try a pencil.
5. Ask the students if the part of the pencil out of the water looks different from the part in the water. Does it
appear bent?
6. The water refracts (bends) the light as it travels from the pencil to your eyes making it look larger than it
actually is. It looks magnified.
7. Let the students try a penny.
8. Ask them why they think the penny looks bigger? This happens when light passes through the water and
refracts.
9. Explain to the students that we can actually SEE the colors of the rainbow when we refract light.
Part 2: Making a Rainbow
1. Fill a flat dish half full of water.
iTEEM Lesson Plan
2.
3.
4.
5.
Put the mirror in the dish so it slants back against the side. Secure it with the modeling clay.
Shine a flashlight on the part of the mirror under the water.
Hold the piece of white paper above the light. A rainbow will appear on the paper.
Put the rainbow away and have the students name each color. Tell students there is an easy way to
remember the order of the color spectrum: ROY G BiV. (red, orange, yellow, green, blue, indigo, and violet.)
Discuss with students that indigo isn't actually in the spectrum of a rainbow. That is why we write it with a
lower-case i.
6. Tell students that water is not the only way to make a rainbow. We can also use prisms.
7. Use a prism to demonstrate how a rainbow can be formed. (Casting the rainbow on a piece of white paper
will make it more visible.)
8. Give students prisms and allow them to experiment making rainbows by using flashlights, and (if time
permits) sunlight.
Part 3: Making White Light
1. We have experimented with separating white light into the colors of the spectrum. Now we will see if we can
combine the colors of the spectrum to form white light.
2. Ask students to name the primary colors (red, yellow, and blue.)
3. Explain that red, yellow, and blue are the primary colors of pigment (or paint), but light has different primary
colors. They are: red, green, and blue.
4. Cover the ends of three flashlights with the red, green, and blue cellophane.
5. Give the flashlights to three students and have them point them one at a time toward a white paper.
Challenge them to mix the primary colors of light to form white light.
Differentiation: (“Describe how you would differentiate this lesson for various learning styles, ESL,
special needs, gifted, etc…”.)
Have class split into two teams: One team will demonstrate reflection, the other demonstrates
refraction. Within each of the two groups, provide a variety of ideas to demonstrate each item and let
students select how to demonstrate in the manner that they understand.
Assessment suggestions:
Types of Assessment: (How will you know what they need to learn and that they have learned it?)
Refraction Ideas:
Summarize what they observed in each demonstration and how refraction was involved
Reflection Ideas:
1. After the presentations have students answer the question, "What makes a rainbow?" in their science
journals.
iTEEM Lesson Plan
The following questions would work well with whiteboards where all students write a short answer to the question. This
provides quick, accurate assessment to guide your curriculum.
If the angle of incidence is 25°, what is the angle of reflection? (25°)
What do we call an object that allows only some light to pass through? (translucent)
Which object will make the best shadow—translucent, transparent, or opaque? (opaque)
Draw light hitting an uneven surface. (Student should draw light scattered in all directions.)
List the colors in order as seen when light hits a prism. (ROY G BIV)
Which color best reflects the colors of light? (white)
Draw light being refracted. (Student draws light refracted through water, or pencil in water.)
Draw a natural light source. (sun, stars, fire, lightning, etc.)
Write whether the following examples are refraction or reflection:
A prism bending light. (refraction)
A straw seeming broken inside a glass of water. (refraction)
A kaleidoscope. (reflection)
The ocean looking very blue under a blue sky. (reflection)
A sea shell looking closer than it really is. (refraction)
Current Instructional Practice (CIP) Level: Select One
Technology Use/LoTi Level (21st century classroom)