Category: NEW TOPIC

Students will recognize volume as an attribute of solid figures and calculate the volume of a cuboid by counting cubic units.

Materials Required:

• Cubes
• Two containers (vase, glass) that can hold water
• Small round objects (Balls, marbles)
• One container that is a cuboid
• Water
• Sticky notes

Introduction

• I started the class by showing two containers, one empty and one filled with water.
• I asked my class how much water they think is in the filled container. Students were guessing using cups as a unit.I recorded and praised their guesses, acknowledging the units they are using.
• I prompted them to think aloud how to measure how much “space” is inside the containers. This is to encourage the students to think and explore this idea to get them to come up with solutions.
• I then showed them a cuboid and asked if it would be easier to measure the space in this cuboid or the glass. This is to make them to wonder.
• Come back to the idea of units. I asked them to work in groups to think of a unit that could measure space inside of objects. Give students 2 minutes to discuss this in groups.

THINK-PAIR-SHARE activity

• Create groups of two and ask each group to discuss the different units of measurement for measuring the space inside the container.
• Prompt the students by asking them if they can use round objects such as balls or marbles to measure the space. Discuss how many balls may fit inside the container and whether they fill the space completely.
• Let students note that since balls don’t fit exactly together, there will be space between them that will not be measured.
• Then pose the question: What shape can work better to measure the space inside the container without leaving any space in between?
• If students can’t think of any, suggest cubes and discuss it.

Guided Practice

• I explained to students that since cubes fit together perfectly we use cubic units to measure the space inside an object, called volume.
• Give the definition of volume: Volume is the measure of the amount of space inside of a solid figure, like a cube, cuboid, cylinder etc. It’s units are always “cubic”, that is, the number of little element cubes that fit inside the figure. Since cubes have three dimensions namely length, breadth and height, the volume is measured in units³
• Each student was given some cubes and sticky notes. They were instructed to make a shape with the cubes. They had to figure out the volume of their shape and write it on the sticky note.  

A cuboid is a 3 dimensional shape.
To work out the volume we need to know 3 measurements.