Lesson video

In progress...


Hi, and welcome back.

Thank you for coming to join me again.

In this lesson we're going to come tremendously good at using the addition and multiplication symbols correctly.

I've got some matching games to have a go at.

We will meet up with some fun friends, and I know you're going to enjoy the next practise task I've got for you.

Let's get started then shall we? In our last lesson, we learned a new written way to represent groups of objects.

By the end we were able to write multiplication expressions because we thought carefully about the number of groups we could see, the number in each group, and the new multiplication symbol to write.

So let's have a look at the practise task I gave you.

So the first challenge was to make groups of objects to match the expression on the screen, and then to write the multiplication expression.

This was how I chose how to do it.

I started by looking at the addition expression, and I noticed that the number six was written three times.

I said to myself, one six, two sixes, three sixes.

There are three sixes.

And that's when I worked out there are three groups of six.

So I grabbed some marshmallows and bowls and made my representation.

When it came to writing a multiplication expression, I knew that the first number represented the number of groups, so I wrote in the number three.

There are six in each group, so the second number in all this multiplication expression needed to be number six.

So here's the second practise activity that I had asked you to go at last time.

We had some buckets of water and each bucket had five litres of water in it.

It was a little trickier because we couldn't see all individual litres of water inside.

I asked you to write different expressions to match the picture, and then to think carefully about what each number represented.

So how did you get up? In this picture we can see that there are four groups of five.

We can write this as five plus five plus five plus five.

There are four fives.

Remember this multiplication expression, four fives, was our new quick way to write our equal groups.

Do you remember what the four represents? Yes, in this picture, that's the number of buckets.

That's our groups.

What does the five represent? The number of litres in each group.

Now remember it's very important that you write your symbol correctly because it helps us to understand the maths.

So even though both symbols help us to represent groups of objects, we use each symbol slightly differently.

We use the addition symbol lots of times when we repeatedly add groups.

For the multiplication symbol, it's just used once.

It is much quicker to use the multiplication symbol isn't it? So to make sure that we're really clear on what each number represents, the four that we see in this multiplication expression means the number of buckets.

And the five that we see represents the number of litres in each bucket.

So for this multiplication expression, we can say that we have got four fives.

Staying like a sedalia.

We're going to carry on matchings of our repeated additions and our multiplication expressions.

We're going to get really good at this.

Yesterday, when I was on my daily walk, I spotted some snails, and they left some trails behind.

They reminded me of one of my favourite story books.

And it got me thinking about snail trails.

Why wouldn't it? If a snail travelled 10 centimetres in the morning, and then another 10 centimetres at lunch time, 10 more centimetres in the afternoon, and another 10 centimetres in the evening, then how many groups of 10 centimetres would his trail be? Ohhh, what do you notice? Yes, some leaves have blown in and covered some of our recorded numbers.

Can we use our skills to work out the missing imparted numbers? How many groups of 10 centimetres should we see? Yes, four groups of 10 centimetres.

So how can we write this? We can see ten plus ten plus, ohh, the leaf is covering them up.

What should it be? Plus ten plus ten.

We can write this as ten plus ten plus ten plus ten.

Four tens.

How else can we write this? Yes, we can write four times ten.

Four tens.

What does the four represent? You're good at this now.

The four represents the groups.

And what does the ten represent? It's the ten centimetres in each group.

Wow, well done.

I've brought a special friend along to help us out.

Do you make a nice three from number blocks? Let's give him a wave.

Hi, Three.

Thanks for coming to help out.

Have a look at three's body.

Can you see that Three is actually one group of three blocks? Three is a group of three.

If you have some number blocks at home, you could pause the video whilst you go and get them, if not you could use pasta, small ties, or even some sweets if you haven't eaten them all.

Or if you would prefer just sit and watch with me.

We know that each number in our addition expression is one group.

So one group of three is one three.

Two groups of three is two threes.

Three groups of three is three threes.

Four groups of three is four threes.

Now we can match these up.

One three is one three.

Two threes is a two three.

Three threes is a three threes.

Can you say the last one? That's right four threes a four threes.

Well done.

Look who else is here today! Hello, Four.

Let's give him a wave too.

What do you notice about Four's body? Yes, did you see Four is actually one group of four blocks? A group of four.

Let's think about how we can write this down to represent what his body looks like.

We can write four, one group of four is one four.

Ohh, four looks little bit different here.

He's still a group of four.

Two groups of four are two fours.

Three groups of four are three fours.

Four groups of four are four fours.

We can match these up now.

Join in with me.

One four is one four.

Two fours are two fours.

Three fours are three fours.

Four fours are four fours.

These different representations all mean the same thing.

So here's a little practise game for you.

The expressions and three have matched up but some have gone missing.

What could be missing? Can you spot what this should be? Perhaps, pause the video and have a little think and then come back to me.

Did you notice that three plus three should match to two threes? Did you also spot a missing addition? Yes, four times three is the same as four threes.

Do you remember how to write it? Three plus three plus three plus three.

Is there anything else missing? Ahh, yes, one three is missing.

One three is Three himself.

One group of three.

Well done.

Have a look at this page.

What do you think the problem could be here? Are the multiplication expressions next to the right pictures? No, I don't think they are either.

Pause the video and use your finger to match the pictures and expressions.

Come back to me when you're finished.

I'll wait here for you.

The first one I noticed was that two plus two plus two plus two should match to four twos.

What else did you see? Correct, one group of three is the same as one three.

Three groups of five are three fives.

And two groups of number block four are two fours.

Well done.

Have a go, everything is now in the right places.

I've changed the arrows here into equals symbols because each picture is with the correct multiplication expression.

They represent the same, so they are equal.

So this is the practise activity I think you're going to have lots and lots of fun with.

This is where you can play a matching game.

Can you match the repeated additions with their multiplication expressions? You could play a pick up two or a snap game.

Maybe try someone in your house to play with you.

Get some bits of paper, cards, cereal box could be good, or possible an old envelope.

Draw a large knots and crosses shape, just like in the picture on the screen.

Write some matching expressions maybe draw the number box too.

Look at these pictures on the screen to show you how to make your own set of cards.

You might need a grownup to help you with this part.

I do hope you have lots of fun playing that game.

You could also make cards with an equal symbol too and then put them in between your cards to show that they represent the same thing, just like we did earlier in the video with the different expressions and the number blocks.

Before next time, you could have a little go at this practise activity.

It's a convince me activity.

Have I got three sixes? You could speak to someone else in your house or just have a little think to yourself, but try and prove whether you have got three sixes or you haven't got three sixes.

Look at the expression.

So here is a final challenge for you.

There are some number missing.

Some of the missing numbers are in the repeated addition expression.

Some of the missing numbers are in the multiplication expression.

Remember all of the knowledge you have learned.

We know that they'll represent the same equal groups, so can you figure out what the missing numbers might be and then can you prove it? You might want to use your bowls, your sweets, some drawings, anything that you'll like that will prove it.

Have fun take care, and I'll see you soon.