Conductors and Insulators
Lesson 5 of 13
Objective: Students will be able to determine what materials are electrical conductors and which are insulators while independently thinking through problems and their solutions.
To set our purpose today, I will begin by reviewing what students know about switches and then ask them, "Does it matter what material is used to build a switch?" Listen to the wonderful conversation we begin to have with claims begin built with some evidence.
As a mini lesson, I will simply show the students how to build a circuit board that is open unless the two wires connect to a conductor. I will then have all of the groups build this board and then come back to the community area for the assignment, which is to use the objects in our test bags (random materials including metal and non-metal items) to determine what conductors have in common.
Once they are able to determine that, they are to take their circuit board around the room and test their hypothesis with other items in the room. A sort of conductor/insulator scavenger hunt, if you will.
This scavenger hunt, and the questioning that I will participate in with the students, is a perfect match for helping students become wonderers and thinkers about science. As students are not given answers in this lesson, they will embark on the scavenger hunt and have to make decisions and connections on their own. This is the real learning in science.
As these students were setting up their investigations, I wandered over to see what they were predicting. I thought the first girl that spoke had a strong reason for her predictions. However, her partner disagreed with her about the screen being a conductor. Listen in to this thoughtful discussion.
I continued to visit with teams and hear what they were thinking, constantly asking for evidence. This is such an important step in the work. I want the students to understand the content, of course, but a larger concern for me is to help them grow into independent thinkers that can ask questions of the world around them and provide evidence for the ideas they construct.
This next group approached me with a dilemma. They had decided that metal conducts electricity and found an item made from metal. However, the whole thing did not conduct. Listen and watch how they try to make sense of this.
Sharing and Closing
To close today, we simply shared some results as a class of surprising or difficult moments and then wrote a definition of a conductor and of an insulator on our anchor chart of facts for electricity.
For conductor, we wrote: Conductors allow electricity to flow through a circuit or an object.
For insulator, we simply wrote: Insulators block electricity to flow through a circuit or object.