# Not Just a pretty 100face!

Check out #hundred face on twitter. This was a trending hashtag in the Maths Twitter Blog-o-sphere (MTBos for short) a couple of years ago.

It’s a great way to play with numbers.

### Challenge On Boarding – Estimating lengths

Unless we are in the building trade, science or engineering, we rarely need a very accurate measurement.

It is good to be able to roughly compare sizes with a standard.  I have a few body standards that I use.

The width of the nail on my little finger is about a centimetre.

The length of the top section of my thumb is about an inch.

The length from the middle of my ch.est to the tip of an outstretched hand is about a metre

Test yourself

Get a straight-edge and choose a length to draw.  E.g. choose to draw 5 cm.

Once you’ve drawn it, test it using a ruler (or Cuisenaire Rods if you have them).

Try this a few times with different lengths.

Do you find this easier with longer lines or shorter lines?

### Challenge On Boarding – Cuisenaire values

How can we tell the value of each rod?

Let’s compare it with the next smallest one (this is red in most Cuisenaire Rod sets but can be other colours also.

You can then compare others using both red and white (and any others that you’ve found the number for)

On Boarding Challenge

Find ways to make the number 7 using 3 rods.

### Challenge On Boarding – Using a table to calculate values

We can use a table to help us calculate the value of a picture.

### The Challenges

Challenge 1 – What’s the value of this picture?

Challenge 2 – Create a hundred square

Challenge 3 – Create your 100 face (Doesn’t have to be a face!)

Download or share all of these challenges with this pdf and let us know how you got on with it by tweeting using #momentofmaths and start to see Every moment is a #momentofmaths.

If you would be interested in joining an online maths club session that explores this or other Maths Explorers’ challenges, our online programme will go live from Monday 20th April 2020. Find out more at https://online.roots2grow.org/