A page from the "Causes of Color" exhibit...

Lesson 1 (All causes)


Immerse your students in the world of color, and have them organize and communicate what they learn using SpicyNodes concept maps. What’s SpicyNodes? It’s a concept mapping and a presentation tool. It’s available as a free online tool, or your school can purchase an Enterprise subscription for the extra convenience of keeping track of your students’ work.

Over the course of this two-week lesson, you will guide your students through ideas about the causes of color, let them research using this exhibit, do hands-on activities, create nodemaps that are intended for other students to use, and record some of their results in their notebooks or your usual classroom mechanism.

The following is a suggested lesson overview and notes. Please freely expand or shorten the lesson to meet the needs of your class.

Lesson overview

Day 1

Start the lesson with pictures of: rainbows, light bulbs, gemstones, a painting, and a laser light show. If you have a projector, you can use this WebExhibit; if you don’t, have students find pictures in magazines the day before you start. Ask questions: “What makes the colors?” and “Why do we see colors?” You can make a list of “What students know” Now, have students explore Causes of Color.

  • Homework: Read DIY to make a light bulb.

Day 2

Start the lesson with an example of a simple nodemap on the projector or white board. Ask questions: “Why is a chart helpful?” and “What can you do with a chart like this nodemap?” Working in groups of two or three, have students create the beginning of their nodemap, “The Causes of Color.” Confirm that each student can do this activity.

  • Homework: “Bring in jars and electrical wire from home.” Have samples on hand to show the students.
  • Before the lesson, we encourage you to make your own simple nodemap to get a feel for what your students are going to do.
  • To set up the nodemaps, go to group set up if your school has an Enterprise membership; or sign up if your school does not.
  • Explain that the nodemaps are a presentation tool, and should be written to the point of view of other kids. Just like journalists and teachers try to use interesting examples, so too should students. Explain to your students that the titles of nodes should be intriguing, such as probing questions, “Why are butterflies colored?” or provocative statements, “Gross! Bug juice in your candy!” or silly statements and rhymes, “Glittering gold,” followed by more serious explanations of the results of their hands-on experiments.
  • Encourage your students to have fun with the nodemaps, customizing the colors and images, and using real-life examples.

Day 3

DIY Making a Light Bulb

Assign a student to be in charge of batteries and another to cut the steel picture wire. Put the directions on the projector screen or on the individual computers. Someone can take pictures of the light bulbs as they give off a glow. Allow students to try some of the variations.

  • Homework: “Choose words from the Vocabulary list that have to do with the light bulb, and define them.”
  • In order to see an example of “Light Made,” examine with the students the materials section of making your own light bulb. If you do not have these materials in your classroom, you can ask students to bring in the jars and electrical cord from home. You can purchase the steel picture hanging wire and batteries. One 6-volt battery for every group of students should be sufficient.
  • The directions for the light bulb activity are very detailed and should be easily understood by students working in pairs. Please note: The wire is lit for a very short time and the wire will be hot. Caution students. Let them try the variations in the activity. Encourage them to try it again at home.

Day 4

Introduce the nodemap they started, and have students add examples of “light made” from this exhibit. Include a picture of the incandescent light bulb they made. When they finish a node explanation for each of the three examples, they should move on to “light lost” and do the same thing.

  • Homework: DIY Activity Make your own Sunset. Pictures of the experiment are a good thing!
  • In order to see an example of “light lost,” you may want to set up the scattering sunset simulation activity in the classroom for any student who was not able to do it at home. Please read about it ahead of time in case your students have any questions. Refer them back to this exhibit, if necessary.

Day 5

Part A of DIY activity Chlorophyll: Prepare the spinach and let it sit in the jars with the alcohol over night. If time remains, students can work on their nodemaps, progressing to “light moved” and three examples of refraction, dispersion, or interference.

  • Homework: Cut coffee filters into five or six inch strips. (The flat, cone shaped style work best.)
  • In order to see an example of “light moved,” examine with the students the materials section of separating a mixture of colors. You may have to purchase rubbing alcohol if your science department does not have any. One bottle should suffice for a class of 30 students.
  • Pairs of students should be able to follow the directions in the activity. Paper towels will work in place of coffee filters. One bag of spinach will be plenty for your class of 30 students. Water left on a sunny windowsill all morning will get warm enough for the activity to work.
  • Students need to write their names on the filter paper or paper towels. This is easily a two-day activity, accomplished by preparing the spinach on one day and placing the filter paper in the jar on the second day. It is important not to let the bands of yellow run off the paper. Pull the filter paper out when the liquid gets near the top of the paper.

Day 6

Part B of DIY activity Chlorophyll: Students put filter paper strips into green liquid and watch the liquid ascend the strip. There will be a distinct yellow-green line and possibly an orange line. Let the chromatograms dry on the windowsill and take pictures to be uploaded,

Day 7

DIY Activity Flame Tests: Follow the directions in the “What to Do” section. Discuss colors of fireworks.

  • Homework: Finish working on nodemap, including the “Vision” section of this exhibit.
  • In order to emphasize that light can be made, another good activity to do with the students is colors of flames. You need household substances like salt, ice melt, and road flares. You do need a gas flame and if you do not have gas jets in a science lab, you should obtain a container of camper’s gas, usually butane.

Day 8

Discuss patterns of colors. Give students time to look at DIY activity Mixing Colored Paints or crayons or markers. See also a history of color theory.

  • Homework: Make a color wheel

Day 9

Using the Vocabulary list, classify the words as light made, light lost, light moved, and vision. Prepare students for the culminating activity using red cabbage juice.

  • Homework: Students need to bring in samples of soaps from home. You need to supply the baking soda and vinegar.

Day 10

DIY activity Red Cabbage Juice: Classify substances as acids and bases depending on the color change. Reds=Acids; Greens=bases Phenolphthalein is a common chemical in high school science labs. Borrow some and test all the soaps again. The deeper the color, the stronger the soap.

  • Homework: Finish nodemaps.
  • The best culminating activity for this unit on “color” is the red cabbage juice and household acids and bases activity. It lends itself to classifying substances and learning which soaps are gentle and mild as opposed to harsh and strong.

Day 11

Lead students in presenting and sharing nodemaps with other students. Summarize the overall lesson on causes of colors. If you have a projector in the room, after you have evaluated the students’ node maps, you can show the best of them to the whole class.

Other tips and activity ideas

  • Use photos! Pictures in a nodemap add interest and demonstrate creativity. Students can upload their own pictures of a light bulb in a jar, for example, or images from Google or Flickr.
  • Make word puzzles. Go to the page for creation of a word search puzzle using some of the vocabulary words.
  • Explore the vocabulary. During a Language Arts or writing time segment, have your students:
    • Group the words in the list as: light made, light lost, light moved, and vision;
    • Use some of the words in sentences;
    • Create a word scramble; or
    • Alphabetize the list.
  • Do some other cool color activities. Your students can try other DIY activities in this exhibit. See making bubbles, mixing lights, and triboluminescence with Wint-O-Green Life Savers.
  • For gifted and honors classes, suggest that they build a nodemap that involves five examples of each category: light made, light lost, and light moved, and vision. They may want to do other DIY activities from the WebExhibit.
  • Share your ideas and experiences. We’d love to have you send us a short note about your use of this exhibit, lesson, and SpicyNodes in your classroom. Let us know what worked, what didn’t, what you changed, and so forth. your comments to us, and we will publish your success story. We also encourage you to publish student nodemaps on your website or in the SpicyNodes Gallery.

Multidisciplinary connections

  • A Biology class can spend time on the structure and function of the parts of a human eye, the structure of chlorophyll and aspects of melanin, and color blindness. Biology classes may also find our exhibit Color Vision and Art interesting, in particular the background about ”What is Color?”
  • A Physical Science class can spend time on the electromagnetic spectrum and the relationship between frequency and wavelength, as well as the laws of reflections and refraction.
  • Environmental Science classes can study in detail the history of artificial lighting with an emphasis on compact fluorescent light bulbs.
  • Art classes can study the history of the color wheel and the difference between mixing lights and mixing paints. Art classes may also find our exhibit about Color Vision and Art interesting, in particular the Marilyn Monroe color changer.
  • A Chemistry class can study electrons and bonding and its relationship to color.
  • A Social Studies class can study the history of color representation.