Mystery Conductors Day 1

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Students will be able to use their current knowledge of circuitry to detect a hidden wire.

Big Idea

Today's lesson will allow students to show what they know about circuits without having all of the materials given to them. They will have to define a problem and solve it as a group, using their prior knowledge.


5 minutes

I pose this question to the students after they gather at the community center. "How would you be able to locate a hidden wire inside of a cardboard envelop?"

Next, I have the students discuss with their shoulder partners what they think they might do to locate the wire without opening the envelop in anyway.  As they discuss, I will listen in to detect the use of terms like: source, receiver, complete circuit, wires, and pathway. 


Mini Lesson

7 minutes

When the students have finished their brainstorming with each other, I show them the supply table available to them (batteries, wires, lightbulbs, motors, circuit boards, and switches).  

I also show them 8 different "envelopes" that contain a wire inside. These "envelopes" are actually two pieces of cardboard that have 4 brads in them, each labeled with A, B, C, or D. A wire is connected between two of the brads between cardboard, so it is hidden.  You can make these board easily. My school purchases the FOSS lessons and materials, so mine were supplied. 

I do not tell the students, in anyway, how to figure out where the wires should be placed, nor do I tell them what materials they will need. 

I simply begin the active engagement by stating their challenge: "Draw a schematic depicting where the hidden wires are in these boards without looking in them or changing the board in any way."  If they locate the hidden wire in one board, they are to trade with another group and keep testing until the time is up.  However, I am assuming we will need two sessions for this activity. 

Active Engagement

25 minutes

As the students begin to devise their plans and begin investigations, I circulate and guide, converse, and prompt. 

In this video, the students are struggling to work as a group. This is my first task.  I ask them to stop "doing" and start talking. When they do, they are able to discuss a plan and then explain why they think it will be successful.  It is so easy for students to get excited and just begin a trial and error approach.  My intervention here helped them slow down and do some thinking up front. 

I was impressed with this group, as they were testing their circuit before they even put the mystery board in the mix.  I liked that they were problem solving the circuit success first, as they were actually controlling variables. 

This group had a very systematic way of testing their board.  However, they were not met with success. They went on to test the components of their circuit, which did work, so they came to me saying the mystery board was "defective". I asked them think about what they could do during the next session to solve this problem. Their solution: "You should take it apart Ms. Marcus, and make sure the connections are tight"!  What a great response. 


Closing and Sharing

10 minutes

This lesson is done in two parts, as I assumed the majority of the first session would be planning. I was happy that the kids took time to test their circuits before actually testing the mystery boards. 

As a closing, I asked two teams to merge and discuss successes and challenges they had today. I will then have them discuss what they will do during our next session.