Ninety percent never makes it up, and it does not vanish
—choose a mode
Every step up a food chain costs ninety percent.
Grass catches sunlight. A grasshopper eats the grass, and about a tenth of the energy in it ends up in the grasshopper. A mouse eats grasshoppers and keeps a tenth of that. By the time you reach the hawk, almost nothing is left — which is why there are so few hawks and so much grass, and why food chains are only ever a few links long. The ninety percent is not destroyed and it is not stored. It goes somewhere, and this pyramid names exactly where.
What this game teaches
The ten percent rule — one step up, and what it costs
Down the whole chain — why the fourth link has so little left
Working backwards — how much grass stands behind one hawk
Where the ninety percent goes — heat, waste and the parts nobody eats
Matter cycles, energy does not — the difference that decides everything
Why chains are short — and why top predators are rare
Standards: MS-LS2-3 · MS-LS2-4 — Grades 6–8 life science
1 · Pick your difficulty
RookieShort chains, round numbers, the pyramid on screen and the ten percent rule written out beside it. Hints on, no clock.
30 levels
VarsityLonger chains and backwards questions, and the rule card comes down. The pyramid stays. Clock on.
42 levels
NationalsNo pyramid at all — just the chain written out — plus five-link chains and awkward numbers. Tight clock, strict scoring.
48 levels
2 · Add pressure (optional)
Clock on
No hints
Take the pyramid away
Strict scoring
Accuracy
0%1 / 420s
Trophic Tax · Living Systems Arcade · Ecosystems 04 — Energy Flow & The Ten Percent Rule Educator’s Arcade · Offline, single-file, no accounts, no data collected.