spectroscope lesson

Build Spectroscopes-

Instructional Objectives-Science process skills- building experimental models. Concepts-Visible light can be see to be made up of the colors of the spectrum, and that different materials have properties that can be identified by the part of the spectrum the give off.
Time Required-40 minutes (may choose to follow up with additional activities on color as either art or science.)
Advanced Preparation and prerequisite knowledge/skills-Purchase diffraction grating sheets, cut to size, gather tubes or boxes for scopes.(preview this lesson for good demo, explanation of materials, and this website for modeling ideas and physics based explanations. Also, this part of that site shows how to use a variety of light sources to see how spectra are really used in science)
Materials- diffraction grating sheets, small tubes or boxes (see choice of plans) information on Spectrascopes and their uses, tape. (for RAFT model, round sticky dots and hole puncher..... a good plan)

Background- Students have spent some time exploring how light is an energy that can be contained and measured as heat, and which can be directed in structured ways by reflection. Now they can actually "take apart" light, and least into the visible wavelengths of the spectrum-RedOrangeYellowGreenBlueIndigoViolet (ROYGBIV....kids like to say that!).

Although this understanding, and this modeling activity are not neccessary for the students to make solar energy work for cooking, it brings their own experiences with rainbow images in the sky, on sprayed water, and on oil-slicked puddles, into the realm of working science. Also, the simple modeling activity and sharing of spectra views further prepares them for the more involved team processes of solar oven building later. Finally, it opens up follow-up learning on many other aspects of light and color, including the amazing process of photosynthesis.

Procedures-
Introduce the idea that light from the sun is "white".... find out what students already know about that, about colors in rainbow like spectra, and raise the question as to whether all light sources have the same colors (this question can certainly come later) Many students will think about the UV Beads activity, and you can reinforce the concept that light has Parts, which materials respond to in different ways- chemicals in the plastic beads react with ultra-violet wavelengths.

Build the spectroscopes- Use the basic instruction sheet, or first preview the website above if the preference is to build shoe box spectroscopes. The RAFT store in the San Francisco Bay area has wonderful kit sets, but you have to visit the store rather than online order/delivery. Here are their "Idea Sheets".... awesome, and their lesson plan for building scopes.

Let students explore- as students are done each will begin finding the lines of the spectrum in their scope.... enjoy it with them as you walk around, give suggestions as needed for get best views..... have some extra sticky dots for them to make different patterns with pin-prick designs.

Let the students keep the 'scopes, or collect for future use.

Review and Extend-Leave about 10 minutes to share out what they discovered, and to either close with the idea that scientists use "spectral analysis" for many very important experiment (usually by burning materials and seeing the flame, or by viewing "starlight" with special spectroscopes).... or prepare them for viewing other light sources on the following day, based on materials at hand and the Exploratorium lesson plan.

http://www.rainbowsymphony.com/teacher-lesson.htm