Hold up a real bag of sugar and a pencil, one in each hand, as you ask this. Take three hands-up answers, not open call-outs. Let the guess about "exactly one kilogram" sit unanswered — the scales will settle it.

Point to each needle position and say the weight aloud. On the 1 kg dial, hold out for the class to notice the top mark is 1000 g — that is the whole lesson: a thousand grams make one kilogram.

On the 250 g and 750 g dials, ask a pupil to read where the needle sits before you confirm. Is that nearer half a kilogram or nearer a whole one?

Pupils measure at their desks with their group's scales — circulate and catch alignment slips on the spot. The class reads aloud and you reconcile any disagreement as you circulate.

Insist on a hand-estimate before the reading every time — the felt weight is what teaches grams vs kilograms. Watch for pupils reading the needle from the side; get eyes square over the dial. Is this a grams thing or a kilograms thing?

This is the practice round, run as a station rotation — four station objects, groups start one at each and rotate on your signal, weighing at their own scales each time. Keep the rotation brisk so every group weighs all four; the class confirms each reading aloud at the end.

The rubber lands in grams, the water bottle around a kilogram — this is where grams-vs-kilograms clicks. For the ordering stretch, ask what they compared: the number, or the unit first. Which is heaviest, and how did you know before you weighed it?