Measurement & Geometry

Chapter 13 | Volume

These are problem solving open-ended questions that require students to investigate problems involving volumes of cubes and cuboids. The tasks can be given at the start of a topic and done as the students gain enough knowledge to complete them, inserted into a topic at an appropriate place or given as homework or extension.

Know the relationship between volume, mass and capacity.
Find volumes of cubes and cuboids using counting cubes and volume formula in non-contextual and contextual questions.

Teaching ideas

Getting started (Getting started sheet 13)
This link displays the Getting started on page 217 to use as a class discussion.

Contain it (Teacher resource sheet 26)
This link displays photos of several different containers such as swimming pool, trailer etc and asks students to discuss how the size/amount of the contents of the container is described and what it means, For example we talk about the volume of a swimming pool - what does this mean?

Cubes
Show some cuboids to the group or class (make them using Multilink cubes or blocks that join together). Discuss the meaning of volume. Ask students if they can think of a way to describe the volume (amount of space each cuboid takes up) of the cuboids using the Multilink cubes.
Computer cubes
Get students to draw cubes and cuboids on the computer by selecting the cube shape and then copying and pasting it to make cubes and cuboids with particular lengths, heights and widths.
What do you know?
Brainstorm what the students already know about finding the volume of a cuboid. Ask individual students to tell the class what they know about volume and then get others to add to it.

Teacher notes

The practicals activities on pages 220 and 223 could be done as class exercises. You could use wood offcuts or plastic containers for the practical on page 223. It may not be realistic to do this activity in the classroom because of the potential mess. You could do the practical activity outside the classroom,
ask students to do the activity at home.
ask students to tell you what to do and you follow their instructions

Students often confuse the units for area and volume. Point out that volume is three measurements multiplied together so the units will have the superscript 3.
If students have trouble visualising in their heads, encourage them to make the cuboids, where possible, using Multilink cubes.
It is important that students grasp that the concepts of volume and capacity are linked and discover that 1 ml = 1 cm³ and that 1000 L = 1 m³.
Note: Activity 2 question 2d asks students to find about how many ml of water there would be if the ice melted. Water expands when it freezes so when the ice melts there will only be about the same number of ml of water as the volume of ice.