# How to measure length correctly

This term we began our new Maths topic – Measurement.

The skills we will be learning in measurement are:

- What is length and how can we measure it?
- Appropriate measuring tools and how to use them
- Units of measurement: millimeters., centimeters, metres and kilometres.
- Perimeter
- Area

To begin with we brainstormed what we thought units of measurement were and what units of measurement we would use to measure certain objects. Here are some examples:

Small units of length are called **millimetres**.

A millimetre is about the **thickness of a plastic id card** (or credit card).

Or about the thickness of 10 sheets of paper on top of each other.

This is a very small measurement!

When you have 10 millimetres, it can be called a **centimetre**.

1 centimetre = 10 millimetres

A fingernail is about **one centimetre wide**.

A **metre** is equal to 100 centimetres.

1 meter = 100 centimetres

The length of this guitar is about 1 metre

A **kilometre** is equal to 1000 meters.

When you need to get from one place to another, you measure the distance using **kilometres**.

The distance from one city to another or how far a plane travels would be measured using kilometeres.

We discussed as a class how to measure accurately. We need to make sure that we begin at the 0 and that the edge of object we are measuring is next to it. Its also very important to hold the ruler straight. We also discussed what the different units of measurement are on a ruler. Check out this video for more information!

Next we took part in a measuring competition as a class.

Our task was to work in groups of 5 and use our rulers to measuring different stops of paper in centimetres. The only hints we had was that no strip in all 6 coloured bags were the same length and the answers would either be whole centimetres like 18cm or 5cm or they were half centimetres such as 21.5cm or 14.5cm.

It was really important to work as a team and make sure we used our measuring skills that we discussed as a class in the previous lesson. These skills included; lining the 0 up with the end of the paper to measure, holding the ruler straight, reading a ruler correctly and using the correct units of measurement.

Watch our video below of us working together as teams by communicating and helping each other and using mathematical language.

IMG_0376 from skye baldwin on Vimeo.

IMG_0374 from skye baldwin on Vimeo.

For the next few lessons our class undertook a mini investigation involving measuring our bodies.

Our first task was to draw a table and record our estimates of the following body parts:

- Around the base of our thumb
- Around our wrist
- Around our neck
- Around our waist
- A body part of our choice.

We then worked with a partner and used measuring tapes to measure each body part. The units of measurement we used were centimetres. We are now getting better and better at estimating measurements each week with some students even estimating the exact measurement!

Next we were given an old saying to read:

**Once around the waist, twice around the neck;**

**Once around the neck, twice around the wrist.**

We had to use the information we had gathered to decide whether this saying was true for us.

We found out that whilst both measurements were not exactly the same as each other they were very very close. We decided that the saying was **close** to being true because of this observation.

Lastly we had to investigate if we could find any other pairs of body measurements that are double or half relationships. Some of us found that twice around the base of our thumb is the same or nearly the same measurement as once around our wrist. Check out some other statements we created that were true to our body measurements!

Dear Mrs Baldwin,

The interesting thing about the task was the body that we measured twice around the wrist and once around the waist my did not equal the same I found that hard.

You could use measment in building and cutting and more

Dear Mrs Baldwin what I found interesting was how much smaller or bigger my waist and my neck was compered to what I thought it was. The examples that I would use measuring in would be if you were getting new furniture so it would fit in the area or when you are doing art and you needed to measure how big the pieces of paper needed to be. From Jasmin.

Dear mrs Baldwin,

what I enjoyed the most about measuring is the body measurement because you actually were able to get your full measurement of certain body parts.

I’s probably be seeing builders measuring timber,bricks and doors or something like that.

from Harrison

Dear Mrs Baldwin what I found most interesting about the maths topic was measuring the length of the whole class

The measurement I see in every day life is clothes designers and shop owners measuring clothes and mothers and fathers measuring their children as they grow up.

Dear Mrs Baldwin,

I like that it was a group activity so we had to work together and I found that interesting because we could see who could get along together and help each other.

If you are a tyre fitter and you may measure the tyres to find the right size to fit the car or a tailor/dressmaker or a Landscaper etc.

Regards Chloe.

Dear Miss Baldwin,

What I found interesting about this task was that we got to measure the length our body parts.

I n the real world I would see someone using length when they are measuring themselves or when they are measuring the length of a room.

From Constantina.