A quick estimation game: see an everyday item · a banana peel, a tin can, a plastic bottle · and pick how long it takes to break down in nature. One wrong answer ends the streak, and your best score is saved locally in your browser.

Where do the decomposition times come from?

From the widely-cited environmental-education tables, principally NOAA marine-debris material. Real decomposition depends on moisture, temperature and burial, so the game uses coarse, defensible magnitudes · the skill being trained is magnitude sense, not memorising lab data.

Can I study just one category?

Yes. The picker on the start screen filters the pool to nature & food items, human-made materials, or everything. Each category keeps its own best streak.

How does it get harder?

Two ways: as your streak grows the wrong answers move closer to the true duration (450 vs 600 years instead of 1 month vs 1 million years), and an extra answer option joins the row.

Can I print it as a worksheet?

Yes. Decay Time supports the printable worksheet generator at /worksheets · each problem prints with lettered duration choices and an answer key, a ready-made handout for environment and recycling units.

How Long Does It Take to Decompose?

Guess how long everyday things take to decompose · from banana peels to glass bottles. JavaScript required.

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