Can You Hear Me Now?

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Students will discover how the telephone has been engineered over a period of time to enable better and more efficient communciation.

Big Idea

Students learn a little bit about the invention of the telephone, Alexander Graham Bell, explore old models of telephones and cell phones and explore the possibilities of the future.

Mr Watson, Come Here!

15 minutes

Hook:  I held up my cell phone, acted like I had a phone message from my 94 year old mom and listened to it. I repeated the message to the kids as they attentively listened. I held up her toy phone and looked back and forth between them saying " Ya know, my mom used to play with a phone that was like this when she was your age, and now she sends me voicemails on a cellphone! Isn't that amazing?"(I just by chance have these phones in my possession! We never took the old cellphones to the recycling place. Who would have ever thought I could have used them for this lesson?)

Making a personal connection with technology is a great way to get their attention for what was coming next! To integrate biography and to help my students connect the past to the future, I started with an engaging video that helps students understand how a telephone came to exist. I asked them to take some notes. They were particularly intrigued by Alexandar Graham Bell's drawings. The video shows his sketches. One student said that she thought it was really cool to see the real drawings! I asked what part of the engineering process Mr. Bell was showing us at that point? They agreed it was the planning part. He had already had a vision.

I asked if they thought he had to test and plan his invention? We discussed how he must have had to change up his ideas along the way. I explained that the reason he had called Mr. Watson was because he had spilled some chemical and was needing his help in the other room. The first sounds on the phone prior to that were thumping noises that were actually the sound of the Morse Code across the wire.  

Many thought that the fact that another person was working on developing a telephone at the same time, was really interesting. I asked if they thought that it happens today? Could two people have a great idea at the same time and invent basically the same thing, even though they never had contact with one another? It was an interesting question that produced a lot of  discussion. As soon as I could feel the lull in the interest of the discussion, I moved to my next part of the lesson. 

Phone Technology Progression

30 minutes

The lesson transitioned beautifully into the next section as one student raised their hand and asked how old phones looked? I told her that she must have read my mind, because I planned that they would wonder. I switched to the next video that goes through the decades of phone development. 

We watched the video from start to finish first. As it progressed to the end showing future phones, they squealed at what they were seeing. They understood completely what was a possibility and it showed in their voices and dialogue. I let it move the lesson along and did not interfere with my questions. The future phone ideas would return in tomorrow's lesson, when they get to design a phone of the future. If I had stopped to ask questions at this point, it would interrupt the flow of their student driven dialogue that was engaging. 

For now, more foundation needed to be laid and so I stopped them at the lull to explain the next steps of the lesson. I asked them to use their science notebooks to note some observations of how phones changed over the decades. I used the white board and drew a T chart, labeling one side "Decade" and the other "Observation." I went back to the SB and located 1910 example in the video, paused it there while explaining that phones without dials were used to contact an operator and that the operator would put the call through. We progressed a little further showing the next phone. I noted that this phone was a replica, but it was a good example of how the dial was added. I went over to my whiteboard and noted 1910 and made descriptions, modeling how they should do their notes. I continued onto 1920. The notes progressed through the decades and we noticed how phones generally changed very little after the hand held receiver was developed. Plastic was introduced and then colored bodies of the phone. But then, suddenly in 1980, the bag phone or portable phone hit the market. We discussed how that would change how people communicated. We made notes about this phone. Under the notes, I had them write the question: Why in the 80's was there such a big change?

No one could answer this question correctly just yet. So, I told them that they would discover the answer after we explore more telephones and they have time to think about it more. I plan on bringing the question back for tomorrow's continuing lesson.

As we moved into the 90's I told them to notice that they were starting to split the decade. What is going on? I asked this question hoping they would start to notice that cell phones were getting smaller and becoming more streamlined. Screens were appearing and things really were progressing rapidly.

Af 2000, I asked them to think about why the decades were being broken up? They couldn't quite grasp that yet, but it planted some seeds about how engineers respond to demands of people. I plan on attacking that in tomorrow's lesson too! Laying the foundations for thinking through questioning  at the right moment, is a great way to really get kids to understand the purpose behind the engineering aspects of science.This whole class discussion was enthusiastic and every child was engaged. I had tapped into a subject with which every student could identify. This supports the cross cutting concepts of connections to the real world and makes understanding engineering a meaningful thing. 

Students did a good job with their notes in notebook. When they began the notes on cell phones, I asked them to list every aspect they could think of that an iPhone could perform. Then I asked them to scan over their notes and figure out what was significant about each decade. The excitement in their voices showed their engagement and their understanding of how amazing cell phones are now. I said, " Wouldn't this just blow Mr. Bell's mind? Can you imagine if he were alive today what he would say about the telephone now!"  

Hanging It Up!

10 minutes

As students finished up their lists of what today's cell phones can do. We discussed how they thought cell phones work. I was amazed at how my student in the video just had thought it through and connected it to what he knows about sound waves. They all are still not sure what really exists inside a cell phone. 

I transitioned the discussion into getting them to appreciate our human ability to dream up things by saying " If you can dream it up, it can exist." 

I told them that when I was a kid, I loved a cartoon called the "Jetsons." Some of my students were familiar with it. I explained that I wanted them to watch one last clip and think about the things they are seeing in the 1960's ( 50 + years ago) cartoon that actually exist today. 

I showed them the Jetsons. We laughed a lot about the toothbrush and the "electric eye" scene. Then the telephone and Jane's mother popped up. I heard them squeal," They invented Facetime?"

I asked, "Do you think the writers had some imaginations back then? Look what they dreamed up and what is real now!" 

I explained that I remember talk of being able to videoconference when I was a kid. We dreamed of it. I closed by saying, " If you can dream it, it can exist. So dream big!"

I assigned them a little reading about how cell towers transmit. I also told them that when they shut their eyes to sleep tonight to think of ways to improve the iPhone or Android. Bring back some great visions for tomorrow's class!