Students represent their circuits by making drawings, and then compare their drawings with others’. They are often hard to interpret. To solve this problem, students learn to use standard circuit symbols and conventions to represent their circuits. Then they learn to light a Light-emitting Diode (LED) from two batteries in series, and construct new circuits using circuit diagrams as guides.
Coin batteries and LED’s:
Provide each student with a coin battery and a red LED.
Pose the challenge: Suppose someone else wanted to make a circuit just like the one you made. Make a drawing of it so they will know what to do.
Post the circuit drawings, and allow everybody to examine them. Then ask:
Standard symbols provide a way to give information in a very small space. If everyone agrees on what the symbols mean, there is no need to explain them each time. Brainstorm examples of how symbols are used. Then introduce the standard circuit symbols that work the same as other symbols. They save a lot of space, and are easy to understand, once everybody agrees on what they mean. Here is an activity to practice interpreting rules and symbols.
Comparing diagrams with drawings:
Ask each student to make a diagram of the same circuit they drew earlier, this time using the standard symbols and rules. Then conduct another Gallery Walk to compare the two representations for each circuit:
Using circuit diagrams:
Circuit diagrams tell you how to make new circuits. The Lesson 3 worksheet presents two activities where students construct circuits from circuit diagrams.