Comparing mass and weight
Compare two objects directly by mass or weight and describe the difference using language such as heavy, light, heavier than, lighter than
What a learner can do afterwards
- Heft two objects and say which is heavier/lighter
- Use a simple balance to compare the weight of two objects
- Describe one object as 'heavier than' another
1 · Read
For objects you can safely lift, hold one in each hand. Compare how strongly they pull down. The stronger pull comes from the heavier object. Ask an adult before lifting anything that might be too heavy.
Heavier means more weight. Lighter means less weight. Bigger describes size, not weight. If two objects weigh the same, neither is heavier or lighter.
When every block weighs the same, a group with more blocks weighs more. These blocks are equal in weight. The group of 6 is heavier than the group of 2. If the blocks have different weights, counting them is not enough.
When lifting two objects in the same way, the one taking less effort is lighter. Name both objects in your comparison: the ball is lighter than the toy bear.
Start with an empty, level equal-arm balance. Put one object in each pan, such as a toy train and a sponge. The heavier side goes down; the lighter side goes up. Level pans mean equal weight.
Size alone does not decide weight. A small object can be heavier than a larger one. Compare their weights by lifting them safely or using a balance. Do not decide from their sizes or colours alone.
Heavy things are harder to lift than light things.
Original lesson, questions and flashcards written for this topic.
Original readings, questions and flashcards written for this topic.
2 · Watch
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