Hello, I'm Mrs. Mehrin and I'm so excited to learn all about analysing data about human height with you.

We are going to do brilliantly.

Welcome to today's lesson from the unit "Human development." Your lesson outcome today is, I can use a line graph to analyse results and make predictions.

Now I know that learning can be a bit challenging sometimes, but that's okay because we are going to be learning lots of new things together and we are going to do brilliantly.

So here are your keywords for today.

Now don't worry about writing these down, because I will be referring to these throughout today's lesson.

But if you would like to write them down, that's absolutely fine, and you can pause the video now and do that.

Fantastic.

Now here are all of the definitions for those keywords.

Now again, I am going to be referring to these throughout today's lesson, so please don't feel like you have to write them down, but if it makes it easier for you to do so, you can pause the video now and jot them down.

Fantastic.

Well done.

So today's lesson is split into two parts.

Let's begin with our first part, which is representing data visually.

So here, we have Andeep.

Now Andeep has been finding out about human height by measuring children of different ages.

So he's been measuring two to 10-year-olds and he has been recording their heights in centimetres.

So Andeep says, "Here is my data.

There are a lot of numbers and I'm finding it hard to see any patterns." How could he make his results easier to analyse? So I'll give you some time now just to pause the video and have a good think about how Andeep can make his results easier to analyse.

Off you go.

Fantastic.

Well done.

So scientists can represent data in visual ways to help them understand and analyse it.

So they can do this by creating graphs using their data, such as bar graphs or line graphs.

So here, we have a bar graph which shows birds that have been observed and the maximum number of birds that have been observed.

And on the line graph, we have the temperature recorded over time.

So let's do a quick check-in of your learning before we move on.

So why would a scientist create a graph using their data? Would it be A, to make their data look pretty? B, to practise their maths skills? Or C, to make their data easier to analyse? So I'll give you five seconds to think about your answer, but if you think you are going to need longer, you can pop this video on pause and come back to it when you are ready.

Off you go.

Fantastic.

Well done.

So the answer is C, to make their data easier to analyse.

Now bar graphs are useful for comparing quantities.

So here, we have a bar graph which is comparing the height of famous towers.

So we've got towers such as Big Ben, the Eiffel Tower, Blackpool Tower, and the Tower of Pisa.

They are used when the data is not continuous or linked to each other.

So Alex says, "Can you see the height of each object in this bar graph?" So I'll give you some time now just to pause the video and have a quick look and see if you can see the height of each object in this bar graph.

Off you go.

Fantastic.

Well done.

Now Sam says, "I can tell really quickly which is the shortest and which is the tallest tower." Now line graphs are useful for showing how things change over time.

And they're used when the data is continuous or gathered over time.

So this line graph here shows how the temperature of a cup of coffee falls over time.

And Alex says, "I can see that the line goes down, so I know that the temperature fell over time." So Alex has measured the temperature in the playground every hour from 9:00 a.

m.

to 3:00 p.

m.

Which kind of graph would be best for showing Alex's results? Would it be A, a bar graph, or B, a line graph? So I'll give you five seconds to think about your answer here.

Or if you do need more time, just pop the video on pause and come back to our lesson when you are ready.

Off you go.

Fantastic.

Well done.

The answer is B, a line graph.

Now Sam counted how many children were in each of the classrooms in her school.

Which kind of graph would be best for showing her results? Would it be A, a bar graph, or B, a line graph? So again, I'm going to give you five seconds to think about your answer, but if you need longer, you can pause the video here and come back when you're ready.

Off you go.

Fantastic.

Well done.

The answer is A, a bar graph.

Now Jacob measured the mass of his pet kitten every month for a year.

Which kind of graph would be best for showing his results? Would it be A, a bar graph, or B, a line graph? So I'll give you some time again to think about this question.

If you need to pop the video on pause, you can do so.

Off you go.

Fantastic.

Well done.

The answer is B, a line graph.

So here is your first task for today.

It says to decide whether each set of data should be plotted on a bar graph or a line graph.

And it says, justify your answer for each one.

So the amount of pocket money each child in Year Five currently gets.

The height of a sunflower measured each week for two months.

And the area of a puddle in the playground measured every 10 minutes for an hour.

So I want you to think about whether or not those three can be plotted on a bar graph.

Can some be plotted in a line graph? But don't forget to justify your answer for each one of those.

So you're going to need to pop the video on pause here and then come back when you've completed the activity.

Off you go.

Fantastic.

Well done.

So let's have a look at what the answers should be and see if you got them correct.

So for number one, it should be represented on a bar graph because the data is not continuous.

For the second one, the height of a sunflower measured each week for two months should be presented on a line graph because the data shows a change over time.

And then finally, number three, where you are looking at the area of a puddle in the playground measured every 10 minutes for an hour, should also be presented on a line graph because the data shows a change over time.

Fantastic.

Well done.

So that takes us on to the second part of our learning today, which is analysing results and making predictions.

So Laura investigated human height by measuring children of different ages.

She worked out the average height for each age and she plotted her results on a line graph.

So she's chosen ages between two and 10 to do her line graph with.

Now what do you notice about the line on Laura's graph? So I'd like you to pause the video here and have a good look and come back, once you're ready, with an answer.

Off you go.

Fantastic.

Well done.

So next, I'd like you to think, can you identify a pattern in her data? So again, I'd like you to pause the video here and have a go at that question.

Off you go.

Fantastic.

Well done.

So Laura wonders why the line on her graph goes upwards.

So that could be what you noticed as well.

Now Sofia says, "I think it's because you collected more data later on in your investigation." And Jun says, "I think it's because the people you measured kept getting bigger." Who do you agree with? Do you agree with Sofia? Or do you agree with Jun? I'll give you five seconds to think about your answer, but if you need a little bit longer, you can just pop the video on pause and come back when you are ready.

Off you go.

Fantastic.

Well done.

So the lines on our graphs go upwards because humans grow taller over time until the end of puberty.

So Jun would be correct with his statement.

The steeper the line, the faster the growth rate.

Now how does the growth rate change over time on this line graph? I'd like you to pause the video here because you will need to look at this line graph closely and see how the growth rate is changing over time.

Then, when you have an answer, just come back to the video.

Off you go.

Fantastic.

Well done.

So Laura's graph shows that the growth rate was fastest between two and four years old.

And Laura says, "Between two and four years old is where the line on my graph was steepest.

My average child grew around 20 centimetres during this time." Now between which years does this graph show the fastest growth? So have a really good think.

Have a look at this line graph.

Remember what Laura had found out about hers.

And I want you to look at this new line graph and come up with an answer for which years does this graph show the fastest growth? So you may need to pause the video here to do that.

Off you go.

Fantastic.

Well done.

So the fastest growth rate is between the ages of 11 and 12 years old because this is where the line is the steepest.

Now Lucas measured some adults and found the average for each age and plotted his results on a line graph.

So here, we have the ages between 20 and 45 and the heights.

Now Lucas is asking the question, "Why is my line flat?" Because when we looked at the other line graphs, there were points where it was quite steep and the growth rate was quite quick.

Why is it not the same here? Why is Lucas's line flat? I'll give you five seconds to think about your answer, but if you need longer, you can pop the video on pause and come back when you have an answer.

Off you go.

Fantastic.

Well done.

Now I want you to look at the x-axis here.

The line on Lucas's graph is flat because humans do not continue growing once they reach adulthood.

So which of these line graphs might show how humans grow from birth to adolescence over time? So remember, adolescence is between 10 and 19.

So which of the line graphs might show how humans grow from birth to adolescence over time? So think about what you've learnt already and then have a go at this question.

I'll give you five seconds to think about your answer, but if you need longer, just pop the video on pause and come back when you are ready.

Off you go.

Fantastic.

Well done.

The answer is A, because we know from birth to adolescence is when a person grows the most.

So that's going to be a nice, steep line.

Now if we look at B, it's going in a straight line, so that resembles more adulthood.

And C is actually going backwards, so it's saying that somebody who is zero is taller than somebody who's older than that.

So we know that it's got to be A.

Now Sofia's line graph looks different to her friends' line graphs.

Why does this not accurately represent human growth over time? Is it because A, humans do not get shorter then taller again? B, the line should be perfectly straight? Or C, line graphs about humans should always go upwards? So have a really good think about that question.

I'll give you five seconds to think about your answer, but if you need longer, just pop the video on pause.

Off you go.

Fantastic.

Well done.

The answer is A, humans do not get shorter and then get taller again, which is exactly what's happening here on Sofia's line graph.

Now scientists use line graphs to analyse their data and make predictions for further values.

So how could you use this graph to predict the average height of a seven-year-old? So I'd like you to pause the video here and have a go at that question.

Off you go.

Fantastic.

Well done.

So we can find seven years old on the x-axis.

So that's the horizontal line, where it says the age, the years.

Now we go up to the line when we find seven and then look across to the height on the y-axis.

It's just like we have there.

Now using our graph, we can predict that a seven-year-old is likely to be around 120 centimetres tall.

How tall do you predict a three-year-old is likely to be? Pause the video here and have a go at that question.

Off you go.

Fantastic.

Well done.

So again, we're going to find the age three, we're going to go up, and then across on the y-axis.

Now using our graph, we can predict that a three-year-old is likely to be around 95 centimetres tall because it falls in between the 90 and the 100 on the y-axis.

Now let's have a quick check-in of your learning so far.

It says, according to this graph, how tall is a three-and-a-half-year-old likely to be? A, around 90 centimetres tall.

B, around 95 centimetres tall.

Or C, around a hundred centimetres tall.

So you may need to pause the video for this question so that you can have a really good go.

Off you go.

Fantastic.

Well done.

The answer would be C, around a hundred centimetres tall.

So to find three and a half years old, you would have to go in between three and four on the x-axis, then go up, and then go across on the y-axis and it would take you to a hundred centimetres.

Now Jun has a challenge for his friends.

And he says, "My sister is 135 centimetres tall.

How old do you think she is?" So how could we work this out using our line graph? I'd like you to have a really good think about this question.

Again, I'd like you to pause the video so that you can have a go.

Off you go.

Fantastic.

Well done.

So let's see how we can find that information out.

So we can find 135 centimetres on the y-axis and look across to the line and then down the x-axis.

So here, we found 135 centimetres.

We're looking across to the line and then we're going to go down to the x-axis.

And Sofia says that she thinks Jun's sister is around nine and a half years old.

And that's because if you look between the ages of eight and 10, nine would fall exactly in the middle of that.

And then there's one more square and the line is going straight down the middle of that square, so it would be around nine and a half years old.

So, "My cousin is 91 centimetres tall.

How old do you think he is?" So again, I'd like you to pause the video here and have a go at that question.

Off you go.

Fantastic.

Well done.

So the answer is, he is around two and a half years old.

Now findings from enquiries can be used to make predictions about things that haven't happened yet.

So Jun says, "Using my graph, can I predict how tall I will be when I am 12?" So I want you to have a really good think about this question.

I'll give you five seconds.

And then we'll come back and we will discuss how Jun can do that.

Off you go.

Fantastic.

Well done.

So Jun is going to need to extend the line on his line graph into the area he doesn't yet have data for, following its existing pattern.

So, "The line goes upwards so I predict it will continue with this pattern for an average 12-year-old." Now using Jun's line graph, or one of your own, answer the questions.

How much did the average child grow between four to six years old? How tall do you think the average eight-and-a-half-year-old would be? Between which two ages is the growth rate the fastest? And what do you predict the average height will be for 12 years old? So I'd like you to pause the video here and I'd like you to have a go at Task B.

Off you go.

So here is Jun's line graph.

Now you may have come up with these as your answers.

For the first one, it would be around nine centimetres.

For number two, around 130 centimetres tall.

Number three, between two and four years old.

And number four, around 140 to 145 centimetres.

Now if you used your own data, then your answers may be different.

Now let's go on to our summary for today.

So we can calculate averages to help us analyse and find patterns in large data sets.

Human height data can be plotted on a line graph to show growth over time.

Findings from enquiries about human height can be used to make further predictions.

Well done, you have worked so hard, and you have really had to use your critical thinking today.

But you have done brilliantly.

Well done.