In this lesson, students will build on the knowledge of circuits that they created in the previous lesson. I begin this lab by providing students with time to review their exit ticket from the last lesson. I ask students to review with a partner or group what it takes to make a complete circuit.
I also introduce the two new materials with which the students will work in this lab. The students will be working with a bulb socket and battery holder; both of which are likely to be unfamiliar to the students. Because I want the students to engage in an exploration of circuits with the new materials, I do not provide them with extensive background knowledge about either the bulb socket or battery holder. Instead, I name and display each material for the students and then begin the lab.
In this lab, I give students the task of creating a circuit using the bulb, battery, two wires, bulb socket, and battery holder. The new materials introduce a higher level of complexity to the design process and test students' knowledge of complete circuits. I provide a set of materials to each student and then give them plenty of time to explore and create. As in the previous lesson, I ask students to demonstrate perseverance and to document each of their design attempts on their create a circuit lab worksheet.
It is common for students to use the new materials incorrectly as they construct their circuit. It is common to see students putting the battery in the battery holder facing the wrong direction (instead of lining up the positive and negative terminals) and to see students not completely screwing the bulb into the bulb socket. If students struggle with creating a circuit with the new materials, I stop the class and discuss the process of trouble-shooting. I do not provide students with specific directions. Instead, I remind students to return to what they know about working circuits and to check each of the materials to ensure that they are correctly assembled.
A video of a student creating a circuit can be found here.
After building their circuit, students have a good understanding of complete circuits. To deepen their understanding of why the light bulb lights up in a complete circuit, I introduce the students to the parts of an atom and discuss how the movement of subatomic particles (in this case electrons) allows energy (in the form of chemical energy) to transfer from the battery to the bulb through the wire. This rutherford model photograph shows the diagrams I draw on the whiteboard to illustrate this concept for my students. There are several student-friendly YouTube videos that explain this concept including this one.
I then guide students to craft definitions for the terms electricity, electron, volt, and ampere and instruct students to add these definitions to their electricity glossary.
To close the lesson, I ask students to complete an exit ticket. The exit ticket asks students to draw a diagram of their circuit and label and describe the movement of electricity in the circuit. I use this exit ticket as a formative assessment to determine whether students can correctly build a circuit and describe the movement of electrons.