Here is a question with no wrong answer yet: roughly how tall is our classroom door? Don't measure it, don't count anything, just picture it and give a number in metres.

Now the harder one: what things about ourselves and our room get measured to a decimal, not a whole number? Your height, your shoe, a bottle of water, your lunchbox on a scale. Where do the decimals hide?

Look at the length reading on the ruler: find where the edge sits between the whole marks and decide what decimal it shows. Then look at a mass reading on the scale and a capacity reading in the jug, and say what each one reads.

Let's read one length together on the ruler before you head to your stations. First we estimate: is this object nearer 5 cm or nearer 15 cm? Say your guess out loud. Then we drag the cursor to where the object's edge stops and read it as a decimal centimetre. Watch closely whether the edge lands on a whole mark or between two marks — that is where the decimal comes from. Estimate before you read.