Learn a little by doing a little
Make an idea click.
Move beyond an answer. Explore visual reasoning puzzles and interactive challenges across all 6 subjects, with instant rule-based verification and step-by-step explanations.
What belongs in each mystery box?
Every mystery box holds the same value. Make the two sides balance.
0 of 7 challenge types explored at this stage
Keep the discovery going.
Turn a little understanding into a fresh page of practice.
Streaks count different challenges solved consecutively in this session and reset after an incorrect check. Repeating a solved question adds no points. Original rule-based practice. Age bands are guidance, not an assessment or curriculum certification.
Practise by subject and stage.
A machine is supplied with 420 J of total energy and transfers 399 J as useful energy output. Calculate its percentage efficiency.
Calculate the percentage efficiency of a device from useful energy output and total energy input.
0 of 4 solved in this round
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