MA 7.02Comparing Weights with a Balance Scale
The child puts objects in the pans of a balance scale to find which is heavier, lighter, or the same weight, then balances an object with counted cubes.
Age 4½Work 2 of 6 in Measurement, Time, and Money
Presentation
- 1
Show the empty balance: 'When the pans are level, both sides weigh the same.'
- 2
Hold an object in each hand: 'Which feels heavier?' Then place one in each pan.
- 3
Point: 'The pan that goes down holds the heavier object.'
- 4
Three-period lesson with heavier and lighter.
- 5
The child compares several pairs of objects and says which is heavier.
- 6
Place one object in a pan and add cubes one at a time to the other pan until the pans are level. Count the cubes.
Extensions, easiest to hardest
- Order three objects from lightest to heaviest using the balance.
- Predict which is heavier before weighing, then check.
- Record how many cubes balance each object.
Control of error
The balance arm: the lower pan holds the heavier object, and level pans show equal weight.
Ready to move on when the child…
- Reads the balance correctly for any pair of objects
- Balances an object with cubes and counts them
Guide note
The Sensorial Baric Tablets are the indirect preparation.