Lesson Notes By Weeks and Term v5 - Grade R

Lesson Video

This page supports the lesson note with a companion video and a short classroom-ready summary.

For class groups and homework, share this lesson page so learners also get the summary, objectives, and full lesson context.

Performance objectives

• Tell the difference between 'long' and 'short'.
• Tell the difference between 'heavy' and 'light'.
• Compare two objects using 'longer than' and 'shorter than'.
• Compare two objects using 'heavier than' and 'lighter than'.
• Put three objects in order from shortest to longest.

Lesson summary

Measurement is an important skill that helps us understand and describe the world around us. In Grade R, we begin by exploring simple measurements of length and mass using comparative language. Knowing if something is long or short, heavy or light, is helpful in everyday life. For example, knowing which stick is long enough to reach a mango from a tree, or which bag of apples is too heavy to carry easily. These basic concepts of measurement set the foundation for more complex measurements later on.

Lesson notes

Length: Long and Short Length describes how far something extends from one end to the other. We use "long" to describe objects that extend a significant distance and "short" to describe objects that do not extend very far. These are relative terms, meaning an object is long compared to something else.

Long: Extending a great distance from end to end.

Short: Extending a small distance from end to end.

Examples: A skipping rope is long compared to a pencil. A pencil is short compared to a skipping rope. A car is long compared to a toy car. A matchstick is short compared to a broom.

Mass: Heavy and Light Mass describes how much "stuff" is in an object. We often use the word "weight" informally, but in science, we are referring to mass. We use "heavy" to describe objects that have a large mass and "light" to describe objects that have a small mass. Again, these are relative terms.

Heavy: Having a great mass.

Light: Having a small mass.

Examples: A brick is heavy compared to a feather. A feather is light compared to a brick. A school bag full of books is heavy compared to an empty school bag. An empty plastic bottle is light compared to a bottle full of water.

How to Compare: To compare lengths, hold the objects side-by-side, aligning one end of each object. The object whose end extends further is the longer one. To compare masses, hold one object in each hand. The object that feels like it's pulling your hand down more is the heavier one. It's important to use objects that are safe for children to lift. Avoid very heavy or awkward items.

Worked example

Length: Imagine you have a crayon and a ruler. Place them next to each other, with one end of the crayon and one end of the ruler lined up. You will see that the ruler extends further than the crayon. We can say that the ruler is longer than the crayon and the crayon is shorter than the ruler.

Length: Let's compare a blade of grass and a stick. If the stick reaches further than the blade of grass when lined up, then the stick is longer than the blade of grass and the blade of grass is shorter than the stick.

Mass: Hold a small rock in one hand and a balloon in the other. You will feel the rock pulling your hand down more than the balloon. The rock is heavier than the balloon and the balloon is lighter than the rock.

Mass: Compare an empty lunchbox and a lunchbox filled with an apple and a sandwich. The full lunchbox feels heavier.

Therefore, the lunchbox with food is heavier than the empty lunchbox, and the empty lunchbox is lighter than the full lunchbox.

Guided Practice (With Solutions)

Question 1: Look at these two objects: a pencil and a book. Which is longer? Which is shorter?

Solution: The book is generally longer than a pencil.

Therefore, the book is longer, and the pencil is shorter. We can physically compare the two objects by placing them side by side to confirm.

Question 2: You have a small toy car and a large school bus. Which is longer? Which is shorter?