Introduction to Elementary Circuits

Michael D. Jackson             W.H. Carter  
                               5740 S. Michigan Ave. 
                               Chicago IL 60637
                               312-535-9205

Objectives:

  1. Children should be able to predict ways to light a bulb.
  
  2. Children should be able to define parts of an electrical circuit.
  
  3. Construct and test models of electrical circuits.

Vocabulary:
  
  1. electrons  2. positive and negative charge  3. conductor  4. energy
  5. generator  6. convert  7. circuit  8. mechanical energy  9. battery
 10. chemical energy

Vocabulary in Spanish:

  1. electron  2. positive et negative charge 3. conductor  4. energia
  5. generador  6. convert  7. circuito  8. energia mecanical  9. batera
 10. energia quimica

Materials:

  1. batteries, D cell  2. bulbs, #48  3. bare copper wire (activity 1)
  2. batteries, IS6 cell  2. bulb, #48  3. copper wire  4. switch (activity 2)

Instructional Prompting:
 
  Stimulate discussion by holding up the materials to be used and asking the 
students to name and describe the function of each.  (If students do not supply 
the information, make sure that these ideas are covered: a battery is the source 
of electrical energy; the wire provides an unbroken pathway for the activated 
electrons from the battery to energize the copper electrons in the copper wire. 
The bulb is placed in the path of the electron flow thus converting this energy 
into light energy.  

  Ask the students to predict how they could arrange the materials to light the 
bulb.  Write several of their predictions on the board and discuss the 
principles of circuits and whether or not their predictions meet the criteria. 

  Students will now be given the materials for activity 1.  After each attempt a 
drawing of their attempted circuit should be made.  This procedure will continue 
for 15-20 minutes or until the students have perfected their technique of 
lighting the bulb. 

  At this point, explain to the students that they have made a circuit with the 
materials.  Review the parts of the circuits, review the criteria of a circuit 
then have volunteers draw on the chalkboard arrangements that made the bulb 
light.  Stimulate discussion by asking, "What are the three parts of the 
circuit?" (a source of electricity, a bulb, and a wire); "In what path did the 
electricity go to make the bulb light?"  (It made a complete path or circle from 
the energy source, to the bulb, and back to the energy source.);  "What happened 
when the path or the circle was broken?"  Have the students trace the path of 
electricity in their circuits when the bulb was on. 

  After thorough discussion of the simple circuit, the concept of a switch is 
introduced as a controlled break in a circuit.  This switch is constructed with 
a small (2in x 3in) poster board sheet, a paper clip, and two brass paper 
fasteners.  The switch must be connected between the (-) term. of the battery 
and the (+) term., with two copper wires connected to the (in) and (out) of the 
switch.  The (in) wire of the bulb was connected to the (out) of the switch, the 
(out) wire of the bulb was then connected to the positive term. of the source. 

Performance Assessment:

  1. Request that all children name the three components of a simple circuit.

  2. Request that all children, while looking at their materials, name and draw 
     each function in a circuit of the materials they have in front of them. 
  
  3. While examining their drawings or reattempting activity 1, have children 
     diagnose the problems with the circuit prior to the successful lighting of 
     the bulb.

Rubric:
  
 3 pts-If students can I.D. all necessary components of a circuit, successfully 
        light the bulb in the circuit and successfully connect a switch to the 
        circuit. 
 2 pts-If students can I.D. all necessary components of a circuit, successfully 
        light a #48 bulb in the circuit. 
 1 pt--If students can I.D. all necessary components of a circuit.