Volume as Addition
Lesson 7 of 14
Objective: The students will be able to explain volume in terms of addition of layers.
In this lesson students will be using their knowledge from investigating volume thus far in order to view volume as addition of layers. They will be using the one of the box dimensions in the previous lesson’s investigation to look at the prism in layers.
As a spring board into today’s lesson I play a quick game of I have, who has with addition facts. I chose to use addition facts because our main focus of today’s lesson is using addition to look at volume.
I print out the I have, Who has sheets and cut them up. I distribute one to each student and we begin to play. I choose a student to start and let the class run the game until they get to the end and the last card.
For this part of the lesson I invite the students to self-discover how to look at volume as addition of layers. Each partnership recreates the 6 x 3 x 4 prism from the previous lesson using base ten cubes. I then pose a simple problem to the students.
We need to create a number sentence for determining the volume of this prism. I would like you to only use the addition symbol in one side of your sentence. There may be more than one way to write this addition sentence. See what you can come up with as you work with your model. Feel free to discuss with your group as you investigate. Make quick sketches of your ideas.
The goal is that students are able to see that the volume of the prism can represented in three distinct ways using addition.
- 24 + 24 + 24 = 72
- 12 + 12+ 12+ 12+ 12+ 12 = 72
- 18 + 18+ 18+ 18 = 72
To wrap up this lesson I facilitate a student led whole group discussion around the conclusions of our investigation. I ask students to think about what they discovered in the lesson and then let the students share and continue the conversation as a class.
As an exit slip for this investigation I ask students to explain volume as addition using words and a model. This gives me an insight into how students are progressing with their understanding of volume.