Make it a wood sandwich!
Lesson 7 of 7
Objective: SWBAT create a stronger piece of wood by utilizing the engineering design process.
I call the kids one table at a time to sit like scientists. I hold up a single thin piece of wood and ask the kids what it is. They yell out, "Wood!" I then suddenly snap it in half. The kids all yell out in excitement. I do this to engage the kids and thinking about the characteristics of a single thin piece of wood.
I ask the kids, "Why do you think it was so easy for me to break this wood?" I choose a random student whose hand is raised to share his idea. He tells the class that it's because the wood is so thin. I respond by telling the class that, "He is absolutely correct! I would love to have you think I am a super strong superhero when I'm not teaching kindergarten, but that isn't true. It's because the wood is so thin that it's weak."
I then pose the question, "How can we make this wood stronger?"
The kids share a variety of answers including wrapping it in duct tape and dipping it in cement. It's always fun to see what kindergartners come up with. Their imaginations are my favorite part!
I then tell them that I am going to ask them to sit at their tables where they will find a box that has pieces of wood just like the one I broke, two bottles of glue, yarn, and a roll of tape.
"Okay, Scientists, your job today is to figure out the best way to make this wood stronger. Your job is to make sure that I am not able to break it. Here are the rules:"
- use only the materials provided in the box
- everyone at the table must participate
- you must work together respectfully
- everyone at the table must make a strong piece of wood
- you may help each other figure out how to make the strongest piece of wood you can
- Each person can use up to four pieces of wood and no more
When I am finished going over the rules, I ask one team at a time to go sit at their tables with their hands in their lap. They are not to touch the materials until they are asked to.
Once they are all seated, I tell the tables to begin working. They are given 7 minutes to complete the task. I set a timer.
As the kids work, I roam the room and ask kids to tell me what they are doing, and how they plan to make the wood stronger. Once they have made a strong block of wood, I test it to see if i can break it apart.
One group learns quickly that tying the wood planks together does not make it stronger because they slip apart. The kids who decide to glue their pieces of wood together ask me to let them dry before I test them.
**I have pre-made samples of what kids have done in the past to demonstrate with in the next section. I prepare them the day before so the glued stacks can dry overnight.
I do the experiment in this way to give the kids a minor experience in engineering and design. I want them to think about the structures and properties of objects and how they can use those properties to their advantage to complete a task.
When the timer goes off, I have the kids put their hands in the air and call one table at a time back to the floor.
I pull out my pre-made samples that resemble what they did with their supplies and I test the integrity of each one in front of the kids.
This is what they saw:
- taped stack- broke apart when tape gave out
- yarn tied- pieces slipped out when I wiggled them back and forth
- glue- held together and was unbreakable
I ask the kids what they can learn from what they saw. I call on random volunteers to share their thoughts as I record them on chart paper.
I then pose this question, "What can we do now that we know this information?"
One student says that we should go fix our wood stacks by gluing them together and taking the tape and yarn off.
That is exactly what I have them do by dismissing them back to their tables one team at a time.
They are experiencing the engineering design cycle for the first time!
Once everyone has successfully glued their wood pieces together, I have them leave the stacks on their tables to dry. I call the tables back to the floor one table at a time.
I use this time to introduce the engineering design cycle to them by having them help me list the steps we took in this lesson. I record the steps in a circle format like a life cycle, which they are very familiar with from an earlier science unit on life cycles.
As we are recording this information, I explain to the kids that the plan part is sometimes done in a model. If we were building a skyscraper, we wouldn't build the actual building until we knew we had everything right in the model.
I then tell the kids that we will be using the engineering design process a lot more in future units.
I do this to get them thinking about learning, planning, building, reflecting and rebuilding to improve the original object.
To evaluate the knowledge students' gained from this experience, I have the table leaders pick up the science journals for everyone at their table.
Once they are seated, I send one team at a time to their tables. The kids are asked to draw and write in their journals about how we did to create a stronger piece of wood on one side of the page and to copy the engineering design cycle on the other.
While the kids are working, I roam the room and ask kids questions to check for understanding like, "How did the engineering design cycle help us make stronger wood?"
"Why are the glued pieces stronger than the others?"
"If we didn't have glue, is there anything else we can use to hold the pieces together?"
I help them clarify their understanding if they demonstrate any confusion or misconception.
Once the kids are finished with their science journal entries, I have them come and sit down once again with their science journals. I have the kids turn to their floor partner and share what they wrote in their journal.
To close the lesson, I choose 3 students at random by pulling name sticks from a name stick can and ask them to take the teacher chair so they can show their journal work to the class and explain what they wrote about.
To extend this lesson, I ask the kids what are some other ways that we could use the engineering design process to make something or improve something.
I ask the kids to think of things that they could make better or that they may want to invent some day. I give them 30 seconds on a timer to silently think to themselves. I then have them turn to their floor partner to share their thoughts for 20 seconds each. I time them so neither partner consumes all the time and this procedure holds every student accountable for sharing.
I explain to the kids that they have a science homework assignment. They are to tell their family about what they would like to create or improve and ask them to help design an idea. They will receive a special prize (usually a small piece of candy) if they bring it back to share with the class.
I've actually had some families get so into this that they design and build a prototype to show the class!