Imagine we have one big pizza to share between two people for lunch. How would we cut it so that it is fair, and both people get exactly the same amount? Hands up: where would you make the cut, and how do you know both pieces would be the same size?

Look at each pizza already cut into equal pieces with one piece shaded. Look at how many pieces the whole is cut into each time, and notice the size of the shaded piece.

Let's try this together. I'll call out a number, and one pupil at the board will cut the pizza into that many equal pieces, shade one piece, and tell us its name. We'll do a half, a quarter and a third. Everyone else: watch carefully and be ready to agree or disagree on whether all the pieces are really the same size.

Today we work through these together on the board: show one half, then one quarter, then one third, then three quarters. So far we have shaded one piece each time. For three quarters, we shade three of the four equal pieces, because the top number tells us how many equal pieces to shade.

What we learned today

• A fraction names equal parts of one whole.
• One half (½), one quarter (¼) and one third (⅓) are all made by cutting a whole into equal pieces.
• The bottom number tells how many equal pieces the whole was cut into, and more pieces means each piece is smaller.

Coming up

Next we will look at the same fractions in other shapes, in lengths and in sets of things, so you can find one half of a chocolate bar and one half of a group of counters too.