I begin this lesson by showing several student-drawn circuit diagrams taken from the student's lab worksheets. When selecting worksheets, I try to choose those which show the circuits drawn in a variety of different ways. Showing student work samples helps students connect what we will learn with what we have already learned throughout the unit. I then ask students to focus only on one component in each circuit diagram (usually the bulb or battery as these are often drawn in strikingly different ways by multiple students). I ask students if all of the bulbs look the same and whether it would be easy for anyone to tell what was in each drawing. I ask student groups to consider whether it would be helpful to have everyone draw the bulb or battery in the same way. If they feel it would be helpful, I ask them to brainstorm a list of reasons why this might help.
I inform students that today they will learn a new language that scientists and student scientists us to make their observations clear and easy to understand. First, I ask students to draw a picture to represent each material on the electrical symbols chart. I remind students that as we saw in their previous lab worksheets, the pictures that each person draws will vary and that a stranger looking at their work might not be able to decipher the meaning of each symbol. I then show students the standardized symbol for each material and have them add those symbols to their chart. I lead the students in a brief discussion about why these symbols might be used for each item and how they might help a stranger understand the circuit that is represented by the symbols. A completed sample can be found electrical symbols example.
For their independent work, I ask students to build any circuit of their choosing. I challenge my advanced and grade-level learners to build a parallel or series circuit instead of a simple circuit to increase the level of difficulty in this activity. Conversely, I encourage my struggling learners to create a simple circuit as this will reduce the complexity of the task and increase their chances of successfully completing the work. After their circuit is complete, I ask students to draw their circuit using the symbols that they have learned. Students record their work on their circuit diagrams lab worksheet. A video of a student explaining her circuit diagram can be found here.
If time allows, I extended this lesson by having students trade their worksheet with a partner and use the student's circuit diagram to construct a copy. This activity is highly engaging and encourages students to stretch the level of complexity in their designs.