# Lesson video

In progress...

Hello, everyone, and thank you for joining me today, here at Oak National Academy.

It's blue skies outside and the sun's out.

And that's putting in a really good mood for my learning today.

So hopefully, wherever you are fingers crossed, the weather is kind to you.

Now in today's lesson, we're going to be reading interpreting line graphs, so that you become more familiar and confident when reading individual line graphs, or comparing two or three different sets of data.

Now before we begin the lesson, make sure that you are in a quiet place without any distractions, and you've got all the things that you need.

So please continue the video and join me in this lesson when you're ready to start.

Let's get going.

To get us in the mood for mathematical learning, and hopefully put a smile on your faces, to start with, I always like to share a maths joke at the start of the lesson.

If you have your own math jokes, and hopefully they're a little bit better than mine, I'm going to give some information at the end of lesson how you can send them in to us here at Oak National Academy.

So watch out for that information at the end of today's lesson.

So today's joke is simply this, why was the number six afraid of the number seven? Because seven eight nine.

And if that doesn't get you in the mood for mathematical learning, nothing will.

Little outline for today's lesson, we start off with our new learning and what we're discussing today will be interpreting line graphs.

which we will discuss and go through together but you by all means pause the video and have a go independently at home.

And then we're going to take our understanding and our content today, our context, I'm going to take it a little bit deeper.

And we're just adding a little extra element to our information and to our understanding.

And then it'll be over to you.

You know, we've got an independent task, which is a lot series of questions based on a line graph for you to interpret.

And then, as always, at Oak National Academy would at the end of the lesson, there is an opportunity to do a quiz in which you can just test yourself to see what are the information has been embedded, and hopefully, you'll feel more confident and familiar with the content of the lesson when you're doing that quiz.

Okay? In order to maximise our lesson and our learning experience today, you'll make sure you've got the right equipment, as always.

So hopefully, you have a pencil, you have a ruler, which will be really important today, and you have a couple of pieces of paper or notebook has been provided by your school.

You'll also see on the screen, little icon for a rubber, a rubber is optional.

And actually I prefer, when I'm doing my math and teaching my maths to see people cross out their work neatly.

Because actually mistakes are a huge part of maths, we don't learn anything if we don't make mistakes.

So in mathematical learning, I like to see mistakes crossed out because it means somebody as reflected, identify the misconception and understand where they need to go right.

And that's fantastic evidence to show that you are learning.

So by all means don't rub out, just put a nice little neat cross, and then carry on with your work.

Okay.

So if you've got that information, and you've got all that equipment, we can make a start on our new learning today.

That we're looking at line graphs again, and just to reiterate, do you're think that I'm going on or do we need line graphs for a lot of information there.

What is the point? A line graph allows a visual representation of information that informs people's decisions, and it gives them visually the information they need.

So for instance, if you want to go on holiday, you may be looking around at locations, and you want to find somewhere that's warmer a certain point a year, or you want to know what the temperature is at a certain time.

So you're going to wait October, how you know, we want to find somewhere that's nice and warm, well you can use line graphs to give you that information.

In this example, on screen, you can see that we're looking at temperature in Brazil.

So say you would like to go on a holiday to Brazil, I've never been, turns out lovely place.

But I don't like it too warm.

So actually, I'm not going to go in January or December 'cause it will be too warm for me.

However, it looks cooler in July.

So actually, that might be the ideal time of year for me to go on holiday to Brazil, if I chose to do so.

Likewise, if you're organising an event, and organisations might look at the information from a line graph to try and help establish the best times to run an event, or the best time in the day, or the best time to cross the year.

So if you're organising a marathon for instance, you wouldn't want to be doing a marathon in Brazil, in January, where it's the hottest, you might again decide that actually June, July or August is probably a better time to do a marathon in Brazil.

Because it's cooler and therefore better for our runners.

So you're using that information and you're making informed decisions.

Okay.

Look at the line graph in front of you.

It's got all the correct features that we need.

It has our X axis, has our Y axis, and it has a title.

What information can we learn from this line graph? What's the data story? And what does the slope tell us about the information being provided? Pause the video if you need a few minutes, if not, let's carry on talking.

First of all, the title said average temperature in Rio, Brazil.

So the title is nice and easy for us to understand that we're looking at data about temperature, and it's in Brazil.

And the X axis, so the axis goes across tells us months of the year.

So it tells us that we're going to be plotting information, or recording information from a 12 month period.

And then on the Y axis, we can see it's about temperature.

So we can see that it's going up, and it's going up in intervals of four, eight, 12.

I also know, because I know the half of four is two, between eight and four is six, I know that in between those intervals of four, it can actually be intervals of two.

So I take my little cursor over here, I can see that all those going up and four, eight, 12, I know that actually, there's also two, six, 10.

So I actually know that these little lines go up in twos, and the large lines go up in fours.

So now two, four, six, eight, 10.

And that's going to be really key later on, and allow us to kind of identify some correct information.

And just to reiterate that in a line graph, although you see one large line, actually a line graph is constructed by large series of little lines, okay? So we you see those little crosses that kind of identify individual separate data points, we connect those data points by using a ruler and draw a nice straight lines between individual points.

It provides the appearance of one large line, but actually it's a series of small lines that connect each individual data point.

Okay.

What can we learn from this line graph? Well we can see that in the UK, where it's generally warmer in the summer, and cooler in the winter in Brazil, it actually starts off high in January, February, in the winter, then it starts to drop.

So it's cooler in the summer months, while it kind of flattens out a little bit.

And then it becomes warmer again in November, December as it heads back to winter.

Okay.

So that's the information we going to do.

We can find out from this line graph.

I went a bit far, I would just dropped back again, to talk about the slope.

The slope talks about increasing and decreasing, And the word increase means that the value goes up, and the word decreasing means the value goes down.

So simply put, we can learn that if our line graph or the line sorts of drop, decreases, the data and values are going down.

So on this example, we can see that in March, the data starts to drop from March, it drops all the way down to June.

So we can identify from that is starting to get cooler.

So from March, April, May, it's dropping in temperature until it levels out in June.

And then from August to December, the data starts to go up again.

It increases so that information increases, so that therefore the temperature is increasing over a period of time.

And that information that is provided allows us to answer a series of questions.

I've got an example on the page, what was the average temperature in Rio in May? What was the average temperature in Rio in May? You need to look very carefully.

Now we need to be very accurate on a question like this.

So first of all, we need to identify May, along the X axis.

And then we need to go up the Y axis or find out where the information might be.

Now I need to be very accurately.

So not only am I going to use it by visually looking at with my eye, I am going to use my ruler to really help here, I'm going to show you what I would do.

I take my ruler, and I place it along with time where May is And I would draw a nice line, I would annotate my paper, and I will draw a line, that goes from May all the way up to that extra point that cross.

Okay, now I'm going to do a line that goes across from that, take the point across to the value.

And I can see that when I draw those two lines on my line, I create a perpendicular line, which means they meet at a right angle.

And that means, that shows me that I've actually identified the correct point.

And then I go across my Y axis side, and I remember I know that it's going up in fours, so four, eight, 12, 16, 20, 24.

And it's between 24 and 28.

So I remember also it was going up in twos because half of four is two, two, four, six, eight, 10, 12, 14, 16, 18, 20, 22, 24 and 26.

So therefore I'm confident that when I draw my lines together, that the average temperature in May is 26 degrees, okay, and I can accurately show that.

estimated it, I guessed it, I've used my ruler, be very accurate to identify it correct.

Okay.

I'm going to put myself out away for a minute and show you that, because I can also annotate the rest of my line graph that allows me to present information or discuss the information in a confident way.

So I've gone across my line different data point, I've just annotated what the correct temperature value is for each month.

Okay, and alongside that, not only have I put there so you can see 31, a little tiny thing to see, we've got 31, 31, 30, 28 for each month.

I've also put these little red arrows going down or up, or an equal sign.

So when I've done that, it can't tell you the story of the data.

So I've shown that each month.

So going down by one means, that between February and March, the temperature dropped by one degree, between March to April, the temperature dropped by two degrees, and so on so forth, and also I put the arrows to go up.

I just want to draw your attention to these equal signs.

Now, what you're seeing, and have you noticed that in June, July, and August, that data and the temperature stayed the same stationary.

Didn't increase, and it didn't decrease, it stayed the same.

So I use this equal sign, because equal means balance.

It means one side is the same as the other side.

These balanced out.

So that means that June is the same as July, and actually June is the same as July is the same as August.

So they've both got equal signs, because across that three month period, the information of the temperature stayed the same.

It was consistent across before you start to go back up again.

Okay, put that out the way.

Now we're going to move on to a talk task.

Now that talk task in our schools we were able to work in groups and in pairs.

That's not always possible if you're at home learning on your own.

However, by all means, we're going to talk about it together, but feel free to pause the video, have a look at the information, and discuss it or reflect on it on your own.

If you've got an adult parent, carer, a sibling or friend, somebody close by, by all means get them over, shown them the screen, and talk about it.

But if not you can do this on your own just by looking carefully at the information.

Here's another line graph slightly different.

And the task for you, is can you use the line graph correctly to complete the table below? You'll notice that the value for temperature other than January, February, have not been filled in, they've been covered.

So can you identify correctly what value for each month should be using the line graph? And then can you think of three factual statements that you can make about the line graph? The facts that you can say with confidence that the line graph shows us.

Pause the video, spend a couple of minutes looking at this line graph now.

Okay.

Let's look at our information.

I can see the table below I've filled in with the values.

And I've gone along and I've found my each individual , individually, so February was nine, eight, nine.

March was 12.

Now what made most of these relatively straightforward is because these little crosses the data was written exactly on the grid lines.

And the grid lines helped me in this example, 'cause most of them seem to be even.

Didn't have anything to be, the intervals are still four, they were fitting that for each grid line was worth two, and then they sit on those.

However, there's a few that I'd like to point out.

Check off the table, see if you're correct, if you've made any mistakes or errors, just go back and have a look, see where your mistakes may have been.

Easy to make mistakes.

I've just pointed out, one of the values in particular.

And that is here, with the cross which is in June.

So let me put that down to one side so it doesn't become distracting.

Okay, looking at June, and June value was 21.

Okay, now I've pointed this out because it doesn't fit, and sit on grid line.

June sits between two grid lines.

It sits between 20, and it sits between 22 and 24, okay? So what I need to identify was that I knew that each grid was going up in two, okay? And I knew that it was between the two grid lines.

Or I thought it was 20 and that was 22, I would know that it will sit somewhere here.

So it must be between 22 and 20, therefore halfway between that is 21.

And that allow me to identify that that was 21, okay? You need to be a little bit more care and that's where again, a ruler would have been useful just to identify exactly accurately where it's sat, okay? But that's why we also have to always double check our X and Y axes, to make sure that the intervals are precise.

So if we've done that earlier, we would have notice that although it's going up in fours, it was gone up two, four, six, eight, and therefore between two and zero will be one, between two and four will be three, and that allows us to be accurate with our information.

Okay.

Now, sure you've come up with a range of information.

I've got a few examples I discussed here.

The first is I know the lowest average temperature is in January.

And we can see that the lowest temperature is eight.

And it is in fact in January.

The reason I know that's a fact, because the evidence there is that it's the lowest data point, there's no other data point lower.

So therefore, it must be the lowest temperature across the year.

I can also.

So you may have pointed out that July has the highest average temperature, because there's no other data point higher than July, okay.

Other facts you may say, you may say that on average, the temperature is colder in the winter than it is in the summer months, you could say that the temperature in April is exactly the same as the temperature in October 'cause they are both at 16.

Okay, you can make my say something yet, May, March, you may say that March is the same as November 'cause they are both 12, okay? There's a range of factual statements that you can make, based on the data.

And although actually identifying some of the ideas are relatively straightforward again, it's always about explaining and having a reason for your information.

So yours is always explaining exactly how you know.

We can take our learning a little bit further now and develop our understanding by adding a new element to it.

So we've looked at two different line graphs today, that plotted average temperature across a 12 month period in the course of the year, in Brazil and in England.

And now we've got one line graph, but we're going to take those data points and put them in the same line graph.

So there is a key in the top right hand corner, that shows me the green line represents the data from Brazil, and the blue line represents the data from England.

Just to double check my X axis across the bottom is still months of the year.

So we're still going across a 12 month period.

And my Y axis is still temperatures, and the value is still going up in fours, and up for twos.

Two, four, six eight, 10, 12.

Excellent, okay.

So now what we're going to do is compare the two line graphs.

Those two sets of data.

Two sets of data represented within one line graph.

So what statements can we make when comparing the two sets of data plotted on the line graph? And like, again, pause the video, spend a couple of minutes discussing or thinking and reflecting on what statements we can make? What are the two sets of data? What are those two data stories tell us within the same line graph? Okay? Well, there's various things we could say and I'm sure even the same, did you for instance, identify that in England it is much colder in the winter months.

So in January, it is eight, whereas in Brazil, it is 31.

So therefore, it is much, much hotter in the winter months of Brazil.

Did you for instance, suggests that it is very similar as in July? So the temperature in July, in England, Brazil is very similar.

I say similar, not exactly the same, because of course, it looks warmer in Brazil.

So in Brazil it's 25 in July, whereas in England it's 24, okay.

You might also say there's a bigger variance in England because the range is greater.

So the range in England goes from 24, which is the highest and eight, which is the lowest.

So the range in England is 16.

Because I take my lowest away from my highest value it's given me the range.

So the range is 16.

Whereas in Brazil, the range goes from 31, between 31 and 25.

So actually in the range of 31 takeaway 25, the range is six.

So that means is actually a lot more consistent across the year in Brazil, where the range is only six, whereas in England, the range is a lot bigger it's 16, which means that the range is very , it's a greater change, okay.

Okay, we're going to move on to another line graph now, which is slightly different, although it's still showing temperature.

Now that day, Saturday, August 6, 2016, might seem like a random date, but it was in fact the very first Saturday of the summer Olympics in Rio in 2016.

Now we're going to look closely, what's different about this line graph? Other than the title, what else is different? Think, that's right.

The bottom X axis, is actually time now, not in months, but in 24 hour clock.

And if you look even more closely, it's intervals of three hours.

Intervals of three hours, where every line represents three hours passing across the day.

How can we describe the temperature as it's recorded here? What does that story if you will, of the line graph tell us? Well, we can look across here.

And again, thinking about our language of increasing and decreasing, we can see that the temperature from midnight decreases ever so slightly, then seems to kind of level off.

And then from 6:00 in the morning, the temperature gradually started to rise, until it hit its highest point, which is about 3:00 in the afternoon.

So the hottest point of the day is 3:00 in the afternoon, then it drops.

So at 6:00pm, it was colder, it decreased, then it levelled off.

So there was a consistency for three hours where it stayed the same, and then by midnight, it dropped, it decreases slightly again.

I'm going to ask you a question, because intervals off three hours now, do you know exactly what happens between the data points? Do you know what happened exactly to the weather within those three hours? And the answer, of course, is no, we don't know.

And three hours is quite a large interval of time.

We don't know, for instance, is it this time, that the temperature went up and down, up and down.

So at seven o'clock in the evening for instance, it may have been a bit warmer.

At eight o'clock, it may have been a bit colder, and then it got warm again.

We don't know.

All we can rely on, is the information that's recorded at different points of time.

So don't get too wound up about what may have happened between the data points, we don't really know.

All we can do is tell a story of the data that is collected.

And what we know here, is that the data is collected every three hours.

And that allows us to plot that information together.

Okay, now time for me to pass over to you.

And for you to have a go at the independent task.

Whether you've got the worksheet that you've managed to print off or whether you're going to follow the slides.

That's absolutely fine.

Remember, pause the video whenever you need.

Give yourself as much time as you require to complete this task and do not give up.

Just focus, be determined and being resilient.

Is okay, if you're struggling.

There is no time limit here.

But here is the instruction for you.

You can see there are four main questions and the line graph in front of you.

Here's the line graph represented in slightly larger form, I just want to point out, you may notice that having increased it, that the bottom interval seen to have spread out a little bit is exactly the same, the intervals are still three hours apart, and cover a 24 hour time period.

So pause the video now and have a go at the task.

And when you're ready to resume, we can come back together and share the answers.

Okay, see you in a few minutes.

Okay, let's come back together and have a quick look at the answers to make sure you're on the right lines.

There aren't too many misconceptions.

So as you can see the first answer, How do we know the hottest points? Well, because the data line is at the highest points across the data, we know between 12 midday and 1500 hours, which is 3:00 pm.

We know it is the same, it's the highest temperature of the day.

The number two statement was not true, because the temperature although it does decrease, finishes at 20 degrees by midnight and 24 hours earlier.

It actually started at 18 degrees or actually there's been increased off two degrees across the day.

Number three, the biggest increase in temperature was six degrees as you can see that occur between 6:00 am and noon.

Noon counts the biggest increase it went from 17 degrees all the way up to 24, so it was an increase of seven degrees.

Following question four, kind of an open question.

Make sure you've got a title in your sketch hopefully, and you've got your axes, X and Y axes correctly labelled.

But hopefully you have data points that look very similar.

Although your story might be slightly different with the rain, for instance, or if extra hot that week, your data points might be higher, and the line might look differently.

But hopefully the line graph will look comparatively similar.

Okay, I will put myself away again, and just remind you that this challenge slide if you want to have go, pause the video, which is optional.

But pause the video, have a go and have a chapter somebody may have done this so again, bring an adult, parent, carer back to the screen and explain how you know the answers.

Okay, we're almost at the end of the lesson today.

And again, I've been really impressed with your focus, it was a lot of information there.

But hopefully, you are more familiar.

And you're more confident when you're reading and interpreting line graphs as a result of today's hard work.

It's just time now for you to have a go the quiz, determine recap, and embed some of that knowledge that you've learned today.

As always, I wish you the best of luck.

But how I know, is hard working as you are that you will not need it.

I just like to remind you that if you're sitting at home with a really excellent piece of work, and you're thinking, yeah, pretty pleased with this today, you can share it with us here at Oak National Academy, and I would love to have a look at your work.

So if you're thinking, yeah, I'm proud of this, I want to send it in, please ask your parent or carer to share your work on Twitter tagging @OakNational and #LearnwithOak.

And I am looking forward to seeing all the hard work that you have been putting in.

Okay, everyone, that brings us to the end of our lesson today.

And you have worked incredibly hard on reading and interpreting line graphs.

I just want to say a big thank you to all of you for your work.

There's a lot of information there but you did really, really well.

And I'm hoping that you go away feeling more confident and familiar when using line graphs.

Okay, I'm going to go outside and enjoy the weather because the sun is still shinning outside.

But I look forward to seeing some of you again soon, here on Oak National Academy.

So from me, Mr. Ward, thank you and goodbye.