Lesson: Models: Volume
SWBAT use a formula for finding the volume of a rectangular prism.
Materials Needed: DN Worksheet, shoe box, linkable counting cubes, GP/IND Worksheet, white board, dry erase markers, and pencils.
Vocabulary: volume, rectangular prism, formula.
Do Now (3 -5 min): The teacher hands out the DN Worksheet which reviews mental math skills with addition.
Opening (2 -3 min): Teacher quickly reviews answers to the Do Now. The teacher should then state the objective, “Today, we are going to focus on calculating the space within a rectangular prism. This space or area is called volume. By the end of this lesson, you will be able to use a formula for finding the volume of a rectangular prism.”
Direct Instruction (8 – 10 min): The teacher begins by writing the following formulas on the board: A = l * w and A = b * h. The teacher then says, “Today we will need to use our knowledge of area formulas to develop a formula for finding the volume of this type of shape.” The teacher holds up show box. The teacher can also pass this box around the class so the students can visually see the space.
The teacher then shows the following chart of questions.
1. How many cubes can be placed along the longer side of the box?
2. How many cubes are needed to cover the bottom of the box?
3. How many layers of cubes are needed to fill the box? How can you tell?
4. How many cubes are needed to fill the box?
The teacher then uses the linkable counting cubes to answer these questions with the student’s assistance.
Then the teacher should remind students that geometric solids such as the shoe box are called rectangular prisms. The teacher then reviews the properties of rectangular prisms on the board/chart.
- A rectangular prism has 6 rectangular faces, 12 edges, and 8 corners
- Pairs of opposite faces are congruent
- Any face of a rectangular prism can be designated as the base of the prism. The height of the prism is the distance between the base and the face opposite the base.
The teacher then draws a rectangular prism on the board and labels the base and the height. (See IND Worksheet for example of diagram).
Then call the students’ attention to the following relationships.
- The number of cubes needed to cover the bottom of the box is the same as the number of squares needed to cover the base—that is, the area of the box.
- The number of cubes in the tallest stack is the same as the height of the box.
- Therefore, you can find the volume of a rectangular prism by multiplying the area of the base by the height of the prism.
Volume of the rectangular prism = area of base * height
Written with variables, this becomes V = B * h
Where V is the volume of the rectangular prism, B is the area of the base, and H is the height of the prism.
Guided Practice (10 min): Students then calculate the volume of rectangular prisms of problem 1 and 2 by creating the shapes with the linkable centimeter cubes. Ask students to explain strategies they sue to solve the problems.
Independent (10 min): The students then complete the rest of the GP/IND Worksheet, problems 3 -5 independently.
Closing (2-3 min): Teacher calls the attention of the students back toward the front of the class to quickly review the answers to the Independent Practice worksheet.
|DN Lesson 17 Starter / Do Now||
|IND Worksheet L 17 Classwork||