Electricity

Marie MCCadd                   Coles Elementary School
                               8441 S. Yates
                               Chicago IL 60617
                               312-535-6550
 
Objectives:

To explain how objects can receive a static electrical charge. 
To describe the effects of bringing objects with like and unlike charges
near one another.
To compare conductors and insulators.
To identify and diagram a series circuit and a parallel circuit.
To explain the function of a fuse.

Materials:

T.V. set, string, chalk, balloons, wool cloth, thread, chalkboard, water
sprayer, size D batteries, battery clips and holders, small bulbs (#41 & #48),
sockets for small bulbs, copper wire, objects to test as conductors, paper
clips, plasticine, and strands of steel wool.

Strategy:

1.  The students will perform the following activities to understand how objects 
    receive a static electrical charge:  Let the string hang about one inch from 
    the front of the T.V. set.  When the television is turned on, the string 
    will be repelled or attracted to the television screen.  Students will 
    inflate several balloons.  They will rub the balloons with a wool cloth to 
    create an electrically charged surface.  These balloons will cling to the 
    classroom ceiling and to a chalk drawing of a shelf on the chalkboard. 
2.  The students will perform the following activities to understand the effects 
    of bringing objects with like and unlike charges near one another: Students 
    will inflate two balloons to the same size and tie a string to each balloon.  
    Both balloons will be given negative charges by rubbing them with a wool 
    cloth.  They will repel one another.  Next, one of the balloons will be 
    given a positive charge.  This balloon will be attracted to the negatively 
    charged balloon.  The balloons will be sprayed with water to neutralize 
    them. 
3.  The students will perform the following activities to compare conductors and 
    insulators:  Using a simple series circuit with one small bulb, each student 
    will test objects to observe which materials permit a flow of electrons 
    (conductors) and which materials do not permit a flow of electrons 
    (insulators).  Each student will list items tested and test results on a 
    chart. 
4.  The students will perform the following activities to understand series and 
    parallel circuits:  After learning how to read a circuit diagram, each 
    student will construct a series circuit and a parallel circuit.  The 
    students will make observations about what happens when one bulb is removed 
    from each of the different types of circuits.  They will also observe which 
    circuits have brighter bulbs. 
5.  The students will perform the following activities to understand the 
    function of a fuse:  Using uncomplicated written directions, each student 
    will make a fuse.  The students will observe what happens to a fuse when too 
    much electricity flows through the wires. 

Performance Assessment:

1.  Using a diagram and sentences, explain how lightning is a form of static
    electricity.
2.  What type of circuits are used in buildings?  Explain.
3.  Describe a safety device that is used as part of a circuit.  Explain how 
    it works.