We're Not Catching Butterflies!! 3D Shapes and Nets
Lesson 12 of 14
Objective: Students will be able to identify and assemble nets for 3D shapes.
For the opening of this lesson, I bring in a box (rectangular prism shaped), and I bring in "nets" cut out of wrapping paper sized to cover the box. One net fits the box, the other is for a pyramid and the last one for a cube.
I explain to the students, I am going to wrap this box. I need to find which paper will fit around the box perfectly. I have three different papers. Can you help me figure out which one I can use?
I hold up the next for the pyramid. The students easily can tell this will not fit the box. I ask them to explain why. They say that it has triangles and the box I need to wrap does not have triangles.
I hold up the second net. This one is a little more confusing, but the students realize that it has all squares and the box has some rectangles.
When I hold up the last net, the students all agree this is the correct net. I show the students how it fits around the box perfectly.
I tell the students that we are going to be learning about nets today. The students are perplexed. I tell them, Not the butterfly kind. All of these pieces of paper are called nets. A net fits around a 3D shape, like a coat. I bet if you think about it, you can figure out what kind of shapes the other two nets fit around. The students share some guesses.
Let's move over to the SMARTBoard and learn some more about nets.
For this portion of the lesson, I use the 3D Shapes and Nets SMARTBoard file. If you have a different type of interactive whiteboard, you can still use this lesson by opening the file inSmart Notebook Express. There is also a PDF you can use to recreate this part of the lesson.
I gather my students in front of the SmartBoard. I have cards with each student's name on. These cards are used for selecting who will come up to the SMARTBoard.
I open the first slide (SMARTBoard Slide 1) with the lesson objective written in "student friendly" terms. There is a content objective and a language objective to help focus on vocabulary expansion for my English Learners (ELs) to be congruent with SIOP instructional techniques. I read these objectives aloud for my students.
I can describe what a net is and what a net looks like for different shapes.
I can tell a friend what net goes with what shape and why.
Slide 2: I can break apart the faces of a 3D shape and lay them flat. This is called a net. I can tell this net is for a cube because it has 6 sides that are all squares.
Slide 3: Would this be a net for a cube? Why or why not? What shape would it be a net for? We discuss the characteristics of the net and what shape would
Slide 4: Would this be a net for a cube? How many faces does a cube have? How many faces are on this net? We use a model of a cube and count how many faces there are. The students understand that there are faces missing.
Slide 5: Now, let's see if you can figure out the nets for some different shapes. Remember, compare the shapes and count the number of faces.
Slide 6: Circle the correct net. Tell how you know it is correct. I invite a student to come up to the Smartboard and circle the correct net. I ask the student to explain to the class why it is the correct shape. I assist with questioning as needed to help the student express why.
Slide 7-9: Continue as above.
Slide 10: It's is now Turn and Talk Time. This is an important element of my instruction that allows my students to practice their English Language skills. Every student has a Turn and Talk partner. I ask them to hold hands with their partner and raise their hands in the air so I know that everyone is partnered up.
I say to the students, Look at this shape. It is one that we have not learned about, but can you figure out which one would be the correct net? The students turn to their partner and begin to talk. The students are pointing to the shapes and explaining to each other. They are really engaged. I call on a to share her answer with the class. She explains that it has to be B because there are rectangles on the shape and A doesn't have any rectangles. She does a great job of explaining it to the class, gesturing and pointing to the faces of the 3D shape.
We now move back to our seats for guided practice.
For this portion of the lesson, the students are actually making a 3D shape using a net. This is not for the faint of heart. You will need patience to do this with the students, but I think it is worth the effort. It really helps students make the connection between the 3D shapes and the plane shapes that form them.
You will need the Nets included with this lesson. Select one net for the students to put together (I save the other one for the choice time.)
I pass out the net to the students and I say, This is a net. We are going to put it together to make a 3D shape. I want you to look at the net and make a prediction about what kind of shape the net will make. I call on a student and the student says it will be a pyramid. I ask the student how he knows it will be a pyramid. He said because it has triangles on it and a pyramid has triangles on it.
I instruct the students how to cut out the net. I show them how to fold the net and put paste on each of the gray areas. I assist the students assembling the net with clear tape as needed.
After the students have the net assembled, we come back together as a group. I ask the students some questions, What shapes do you see? How many of each shape do you see?
The students really enjoyed this activity and are asking to do another shape. As I said, I saved the other for the students to do during choice time. There are many websites that have downloadable nets of different 3D shapes if you want some to put into math centers.
We clean up for independent practice.
For independent practice you will need the 3D Shapes and Nets Independent Practice included as a PDF with this lesson. I run the copies back to back. It is also to have 3D shape manipulative for the students to look at during this lesson.
I distribute the activity sheet to the students and tell them. We are going to use our smart kindergarten brains to figure out what net is the correct net for a 3D shape. You will need to look at the shape and then look at the net. Look for the net that has the correct shapes and the correct number of faces. When you find the right one, circle it. I will put the 3D shapes on your tables for you to look at if you need help finding the correct net.
The students begin working and I am AMAZED. They are doing a great job with deciding which nets go with which shape. See Video. When they bring up their paper for me to check, I question them on why they chose the net that they did. This is excellent practice for the students to use their academic language. I also get to witness their understanding of a very complex concept.