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Age 11 to 14
Challenge Level

Have a look at the sets of four quantities below. Can you rank them in order from smallest to largest?

To help you to decide on your rankings, you may need to find extra information or carry out some experiments.

Can you provide convincing evidence of your final rankings?

Number of
Mars bars with the same total weight as your whole class
Steps when walking at a leisurely pace for 1 hour
Stitches in a handknitted jumper
People at a cup final in a large stadium


You can hop in 5 seconds
From the top of a 6 storey building to the ground
The distance from the penalty spot to the goal on a football field
A car can drive on $1$cm$^3$ of fuel


That a pet rat lives
For light to reach us from the nearest star other than the sun
Between two football world cups
For all of the red blood cells in your body to be replaced....10 times

Of a racehorse running at maximum speed
Of the fastest sprinter in the world
Of the fastest cyclist in an Olympic cycle sprint race
Of a bus going past the school

Of a standard family car
Of a million cubic centimetres of water
Of a team of international male rugby players (15 players)
Of enough potatoes to make chips to feed everyone in the school for a week.

Of the sheets of paper in a ream (500 sheets) of A4.
Of the floor of the classroom
Covered by 5 litres of paint
Of fabric needed to make school uniforms for the whole class.

Volume of water
In a half-filled bath
Used in a 10 minute shower
Used in 5 dishwasher cycles
Used to flush the toilet 20 times


Perhaps you might like to make 4 ranked quantities of your own to challenge a friend.
For more advanced science, see Approximately Certain