```How Smart Are You About Electricity, Batteries And Conductors?Lorraine Epps                  Douglass Math and Science Academy                               543 N. Waller Street                               Chicago IL 60644                               (312) 543-6176Objectives:Students will:                             - identify a battery and how it works.- identify how a flashlight works. - understand the relationship between a battery and electrons.- conduct a test to determine what materials are the best conductors.       (This unit will take two to three weeks)       Grades 3-8Materials:   Overhead projector and transparencies of all activities.Activity 1.  pennies and dimes or aluminum foil, paper towels, water, salt, vinegar, lemon juice and an ammeterActivity 2.  signs and small pieces of colored paperActivity 3.  D-batteries, 1.5 V bulb, masking tape, wire, aluminum foil andmaterials for decoratingActivity 4.  batteries (1.5 or 6 V), bulb (1.5 or 6 V), wood(2 by 6 ins.),4 feet of insulated copper wire (2 feet for each side), two pencils with eraser tips, two clean head thumbtacks, and a number of objects to be tested  Strategy:   Activity 1:            MAKE A BATTERYStudents will identify a battery and how it works.                  Teacher will demonstrate how to make a "VOLTAIC PILE" (named after the inventor  of the battery). Students will fold some paper towels about 1 inch square, soak them in one of the solutions with a 1.5 glass of water, by placing a dime, foil and penny on each side of the moistened towel, making a single cell, then connect your cell with wire on both ends of coins to ammeter.  Students will notice needle moving thus indicating that there is a flow of current.Next, students will make more cells piles, connecting them together to see how great the voltage will become.  Students will record data as they add cells and take piles apart when finished so coins will not corrode. Activity 2:            GAME:  PATH OF ELECTRONSStudents will stand in a circle to show how electrons work in a battery called a circuit, (a drawing of a battery showing the path electrons flow).  At the top of the circle, one student will be marked negative (-), another will be the positive (+) end of the battery.  A third student will be the switch, another one the bulb, and the rest of the students will be the conductors.  They will have pieces of paper marked electrons.  Students will start passing the pieces of paper around as shown on drawing.  When the switch goes out of the circle, the light will go out.  (This will show the current of electrons flow around and around the circuit as long as the switch is on.  When the switch goes off, the current stop and the flow of electrons will stop and the light bulb will stop glowing.)                                                   Activity 3:            MAKING A FLASHLIGHTStudents will make a flashlight to see the relationship between a battery and conductors.  Each students will be given materials needed to make a flashlight. First, cut tubes length-wise to fit batteries, then cut a piece of wire (strip bare the insulation), the wire should also be cut longer than the tubes.  Make sure wire is connected to the battery and the bulb.  Then use the aluminum foil as a conductor.  If all connections are correct, current is complete and the bulb will light up.  Students can decorate flashlight any way they choose. Activity 4:            CONDUCTIVITY TESTINGStudents will construct a conductivity tester.  They will learn how to connect one of the terminals of the battery to the bulb assembly (a flashlight bulb in a socket mounted on  a piece of wood).  One wire from the battery terminal and the other wire to the bulb assembly are to be connected to become the test probes.    Wrap the wire around two clean-head thumbtacks (six times).  Push them firmly into the erasers of the two pencils.  When you apply testing probes to each object, the bulb will light up to show you that all metal objects are conductors of electricity.  The bulb will not light up if objects are not good conductors. Students will make a chart to list and show good, poor and non conducting objects.  Then list each object on different color pie-shaped papers.  Mount them on a wheel to visualize the percentage for each category.  References:

Graf, Rudolf F., Safe and Simple Electrical Experiment
Strongin, Herb, Science On A Shoestring
Introduction to Physical Science:  Addison-Wesley (1988).         ```
Return to Physics Index