Lesson video

Hello, I'm Mrs. Kaylee, and I'm going to be your teacher for today's lesson.

We're going to be learning about comparing objects or items using mass.

So let's have a look at today's learning outcome.

Here's the outcome of today's lesson.

So by the end of the lesson you'll be able to do this.

I can compare items or objects according to their mass.

This means that we're going to find out how heavy or light an object is.

Here are keywords for today's lesson.

Can you say them after me? My turn, heavier than.

Your turn.

My turn, lighter than.

Your turn.

My turn, the same.

Your turn.

My turn, equal to.

Your turn.

Well done.

We'll be using these words when we're comparing items using mass.

Here's the outline of today's lesson.

First of all, we will compare mass and then we will compare items that are equal to each other in mass.

Let's have a look at the first part of the lesson.

Here are some children that are going to help us with our lesson today.

We've got Sofia and Jun.

What do you notice here? Can you see the balloon and the tree? We measure mass to find out how heavy something is.

We can compare mass using the words heavier than or lighter than.

Which one is heavier and which one is lighter? Here are some stem sentences to help us.

The (hums) is heavier than the (hums) and the (hums) is lighter than the (hums).

Which word do you think goes on in the gaps? That's right, the tree is heavier than the balloon, and the balloon is lighter than the tree.

How do you know? Have you ever picked up a balloon before? They're very light, aren't they? I don't know if you've tried to pick up a tree before.

I've got a tree in a pot in my garden.

It's quite heavy.

Most trees are in the ground, aren't they? So you wouldn't be able to pick them up.

They are very heavy.

Here we've got an elephant and a mouse.

Which one is heavier and which one is lighter? Here are stem sentences to help us.

The (hums) is heavier than the (hums).

The (hums) is lighter than the (hums).

Which words go on the lines? That's right, the elephant is heavier than the mouse, and the mouse is lighter than the elephant.

How do you know? Have you ever picked up a mouse before? My friend's got a pet mouse.

They're very light.

I've never tried to pick up an elephant before, but I should think they're quite heavy, aren't they? What do you notice here? Can you see the stone and the leaf? Which one is heavier and which one is lighter? You can use the stem sentences to help you.

That's right, the stone is heavier than the leaf, and the leaf is lighter than the stone.

How do you know? Have you ever picked up a stone and a leaf before? Stones are usually quite heavy, aren't they? And leaves are very light.

Even though the leaf looks bigger than the stone, it's still lighter.

We could hold these objects to see how they feel.

So the heavy one, you'll be able to feel it in your hand, make your hand go down a bit more.

And the leaf, the lighter one, you might not even be able to feel it, it's so light.

Sometimes we are able to compare mass when holding objects.

You could try holding two objects in your hands to see which one feels heavier and which one feels lighter.

Jun said, "The stone feels heavier than the leaf." Sofia said, "The leaf feels lighter than the stone." Jun said, "Even though the stone is smaller, it feels heavier." Sofia said, "Even though the leaf is bigger, it feels lighter." Do you agree? Let's have a look at these objects.

We've got a twig, a conker, and a brick, and it says sometimes we are able to compare mass when holding objects.

Have you ever held these objects before? Jun said, "The brick feels heavier than the conker." Sofia said, "The twig feels lighter than the conker." Do you agree with them? Let's check your understanding.

Jun and Sofia are comparing the mass of a feather and a stone.

Jun said, "The feather is bigger, so it must be heavier than the stone." Sofia said, "The stone is smaller, but it is heavier than the feather." Who do you agree with? Perhaps you could try this with some objects.

If you can find a feather and a stone, you could compare the mass of those objects and see which one is heavier and which one is lighter.

So pause the video and have a go.

Who was correct? That's right, it was Sofia.

The stone is smaller, but it's still heavier than the feather.

Let's check with some fruit.

So here we've got some fruit.

We've got a cherry, a banana, and a pineapple.

Can you compare the objects? You might have some fruit like this at home or at school that you could compare.

Can use the stem sentences to help you.

Pause the video and have a go.

So I had a look at the fruit.

First of all, I compared the pineapple and the banana.

The pineapple is heavier than the banana, and the banana is lighter than the pineapple.

Did you see how the words swap around when we changed from heavier than to lighter than? Then I had to look at the pineapple and the cherry.

The pineapple is heavier than the cherry, and the cherry is lighter than the pineapple.

See how the words have swapped around again? Then I had to look at the banana and the cherry.

The banana is heavier than the cherry, and the cherry is lighter than the banana.

How did you get on? Here's a task for you to have a go at.

Can you compare the objects here? Use the words heavier than, lighter than, and equal to.

We've got a bike, a car, and a house.

Can you use the stem sentences to compare two of the objects? Here's your second task.

Can you find five objects that feel heavier than your book? There's a stem sentence there to help you.

The (hums) is heavier than the book.

Then can you find five objects that feel lighter than your book? And again, we've got another stem sentence, the (hums) is lighter than the book.

So pause the video and have a go.

How did you get on with the task? So first of all, we were comparing the objects.

You might have said the house is heavier than the car, and the car is lighter than the house.

You might have said the car is heavier than the bike, and the bike is lighter than the car.

You might have said the house is heavier than the bike, and the bike is lighter than the house.

How did you get on with this task? Did you find five objects that feel heavier than your book? So you might have found things like I did.

I found a chair, a table, a bag, especially when it's got lots of things in, pencil pot, and a water bottle, especially when it's full of water.

And then we asked you to find five objects that feel lighter than your book.

You might have found things like me.

I found a pencil, a rubber, cube, a pen, and a piece of paper.

How do you know that they're heavier than or lighter than your book? Did you put them in your hands to see which ones feel heavier and which ones feel lighter? Well done.

Let's move on to the second part of the lesson.

We are going to compare items that are equal to each other in mass.

What do you notice here? Can you see the two balloons? We can compare mass using the words heavier than or lighter than.

We can also compare mass using the words the same or equal to.

Which one is heavier? That's right.

The green balloon has the same mass as the blue balloon.

The mass of the green balloon is equal to the blue balloon.

How do you know? Have you ever picked up a balloon before, compared it to another balloon? You could try it if you've got some.

They feel about the same.

Which one is heavier here? Can you see the two cars.

You could try it with toy cars.

Here's a stem sentence to help us.

The mass of the blue car is equal to the mass of the red car.

The red car has the same mass as the blue car.

How do you know? Did you try it with some toy cars? Did they feel about the same mass? What do you think will happen when we put these objects on the scales? Can you see a leaf and a stone? Sofia's going to help us put them on the scales.

She said, "Sometimes we can weigh objects to compare them." These are called balance scales.

Sofia has put the objects on the scales.

What do you notice? That's right.

The scales have moved.

Remember, we can compare mass using the words heavier than, lighter than, or equal to.

Sofia's noticed that the balance scales moved.

The heaviest object will tilt the scale downwards.

The lighter object will rise upwards as the scales move up.

Which is heavier and which is lighter? You can use the stem sentences to help you.

That's right, the stone is heavier than the leaf, and the leaf is lighter than the stone.

How do you know? Can you see that the stone has moved down on the scales, and the leaf has moved up? So the heavier object makes the scales move down.

What do you notice? Here we've got a stone and a twig.

Which one is heavier and which one is lighter? Remember, we can compare mass using the words heavier than, lighter than, or equal to.

Which one is heavier and which one is lighter? You can use the stem sentence to help you.

That's right, the stone is heavier than the twig, and the twig is lighter than the stone.

How do you know? Did you see that the stone made the scales go down, and the twig made the scales go up.

So the stone is heavier than the twig.

What do you notice here? Can you see the twig and the leaf? Remember, we can compare mass using the words heavier than, lighter than, or equal to.

When the objects have the same mass, the scales are balanced, so the scales haven't moved because they've got the same mass.

So here's our stem sentence.

The twig has the same mass as the leaf.

The mass of the leaf is equal to the mass of the twig.

How do you know? The scales are still balanced, aren't they? So we haven't got one side gone up and one side gone down.

It has stayed the same.

So the two items have got the same mass.

We are going to check your understanding.

Who is correct? Jun said, "The elephant is heavier than the mouse." Sofia said, "The elephant is lighter than the mouse." Who do you think is correct? That's right.

Jun is correct.

The elephant is heavier than the mouse.

I can see the elephant has made the scales go down.

The heavier object will tilt the scales down.

Who is correct this time? Jun said, "The leaf is heavier than the feather." Sofia said, "The leaf has the same mass as the feather." Who do you think is right? That's right.

Sofia is correct.

The leaf has the same mass as the feather because the scales are still balanced.

Who is correct this time? Jun said, "The leaf is lighter than the stone." Sofia said, "The leaf has the same mass as the stone." Who do you think is correct? That's right, Jun was correct this time.

The leaf is lighter than the stone.

I can see that the stone is much heavier than the leaf, and it's made the scales go down.

The heavier object will tilt the scales down.

Here's a task for you to have a go at.

Can you compare the mass of two objects? Which one is heavier and which one is lighter? Here we've got some pictures of a stone, a twig, a conker, and a leaf.

Can you compare two of the objects? You could use real objects if you can.

Here's your second task.

Can you find five objects that are about the same mass as your book? There's a stem sentence to help you.

I think the (hums) weighs the same as the book.

And think about, how did you decide? Pause the video and have a go.

Get on with the tasks.

So first of all, we were comparing these objects.

You might have said, "The twig is lighter than the conker.

The leaf is lighter than the conker.

The leaf is lighter than the stone.

The twig is lighter than the stone." You might have also said, "The conker is heavier than the twig," "The conker is heavier than the leaf," "The stone is heavier than the leaf," or, "The stone is heavier than the twig." What else did you find? Did you try it with your own objects as well? How did you get on with the second task? I asked you to find five objects that are about the same mass as your book.

You might have found things like this: a pencil case, a ruler, a jumper, a shoe, or some cubes.

What did you find, and how did you know? Did you try it out in your hands to see which ones felt like they had about the same mass as your book? Did you find the same answers as your friends? Why or why not? If you chose a book that's heavier than your friend's book, you might have found different objects, but if you chose the same sort of book, you might have found the same objects.

We've got to the end of our lesson today.

We were comparing items using mass.

We found out that items can be compared according to their mass.

The words heavier than, lighter than, the same as, and equal to can be used to compare the mass of objects.

Balance scales can be used to compare the mass of objects.

Well done, everyone.

See you next time.