But are they all the same kind of four-sided shape? Hands up: what is different about the window and the kite?

Five four-sided shapes, one at a time. For each one we ask the same three questions before we name it: Which sides are equal? Which sides are parallel? Are the corners right angles?

Two sides are parallel when they stay the same distance apart all along and never meet, like two rails of a train track.

Look at the square and the rectangle together: both have four right angles. What extra thing does the square have that the rectangle does not?

Now a slanted one. Watch what happens to the right angles when a shape leans over.

Last, one more leaning shape. This one keeps its opposite sides equal rather than all four, so look carefully at what makes it different from the rhombus.

Each time, say what stayed the same and what changed.

Today you learned

• Every four-sided shape is a quadrilateral, but its name comes from its properties.
• Check three things to name one: equal sides, parallel sides, and right angles.
• A square is a special rectangle — it follows every rectangle rule and adds equal sides.

Coming up

Next we look at polygons with more than four sides — pentagons, hexagons and octagons — and sort them into regular and irregular.