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To turn the "Simple Circuit with Switch " diagram model below into a working circuit, gather the following.

Ingredients

• Printout of the above "simple circuit with switch" page
• scotch tape
• masking tape (not duct tape)
• 4 inch or so sheet of aluminum foil (heavy duty preferred)
• a couple of medium size rubber bands ; wider rubber bands are easier to work with.
• an LED (Light Emiting Diode) - Radio Shack sells a pack of 20 for about $2.50 but you can also buy single ones as well.
• Pair of AA batteries (AAA and other pairs batteries that add up to 3 volts will work as well but not for as long and will be harder for small hands to control.)
• A storage container for the parts and/or printout, which could be: a pizza box; Tupperware plastic container; or 3 hole plastic sleeve with zipper.

Procedures

Path

Masking tape will be laid on the aluminum foil to create a set of strip that will be used for wires.

1. Tear of a sheet of aluminum foil that is about 8 inches long.  There will be some foil left over.
2. Place the foil on a flat surface or work area.
3. Place a strip of masking tape on top of the long side of the foil . Place it in such a way that the foil is right next to the edge of the long side, and extending beyond the foil and sticking to the surface area at each end of the masking tape.
4. Place another stip of masking tape immediately next to but NOT overlapping. The closer you place the next strip of masking tape without overlapping the better.
5. Do this again, and again, so that four pieces of tape are now pressed on top of the foil.
6. Take your fingers slide them down the tape to cause it to press harder against the foil to get a better connection.
7. Peel up the first three tapes one at a time. Just peel back the outside masking tape piece and it lifting it up the foil will stick to it and create a long wide wire. Leave the fourth one stuck to the table so that it is ready to be used to make more wires if needed.
8. Put the "wires" down on the diagram printout. Use scotch tape to hold them in place. When the power or battery holder area is reached, leave some length of foil that will extend over the ends of the battery.

Power

There are many sources of electrical power that can be used. For now, a pair of AA batteries (3 volts) connected in series is easiest to assemble.

1. Stand the first battery upright. Place the second on top of it so that the correct negative and positive ends connect.
2. Wrap a piece of masking tape tightly around the two batteries. Each battery is 1.5 volts and in series, two together make 3 volts.
3. Place this power source on the diagram in its proper place.
4. Use the rubber band to press the pieces of aluminum foil over the ends of the battery. It is critical that the metal side of the wires touches the batteries.

Switch

The switch is nothing more than an aluminum foil drawbridge. The diagram shows it extending out to one side, but not really. It should be created so that one part of the foil folds slightly into the air and extends over a piece stuck to the paper. One of the foil strips should be aligned so that the metal sides of each strip will touch when the top strip is pressed.

1. Tear a piece of foil wire so that it will extend from the Job or LED area to the place for the switch.
2. Fold the end into the area so that it makes a kind of "draw bridge" that can be pressed. Scotch tape this into place.
3. The end coming from the battery should be taped to the paper but in such a way that metal from the top piece can press against the metal from the bottom piece.

Job

1. Take an LED and bend each of the legs at a 90 degree angle.
2. Place the LED so that one leg touches the piece of foil  on one side and serves as an electrical bridge to the other leg touching the other piece of wire.
3. Scotch tape each leg into place.

Test

1. Press the switch and the LED should light.
2. If it does not light, pull the battery out and reverse it. The positive and negative ends of the LED must be in alignment with the ends of the batteries.

Pedogogy - So What?

• Social Studies. Turn out the lights in the room. Use the switch to send some Morse code using the light of the LED. You may need to look up the Morse code patterns on the Web. Ask students to look up the history of Morse and his code. Time how long it takes to send one word and get it correct across the room between different teams. Try a short sentence and compare times.
• Science. This is circuit in which the batteries are connected in serial which adds the voltage. Ask students to come up with ways to demonstrate the difference between serial and parallel circuits given the materials that have for this project. What are other electrical examples in the classroom or elsewhere of the use of a simple circuit with a switch? How do circuits help scientists and mathematicians with real world data collection?
• Information Literacy. Ask students to consider the advantages and disadvantages of this form of  communication. Is it still useful today? Can they find web page or other examples of its current use? How has computer technology had an impact on Morse code?
• Art. How can the color and texture of the aluminum foil, with the color and light of the LED, combined with other materials, be used to enhance or to become an original artistic creation? Try distributing some styrofoam hamburger containers and ask students to use their materials to decorate them as puppets or something else. Visit a museum of modern art and look for examples of sensors and electronics combined to create interactive art compositions.