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River Mystery cover art, a science game for Grades 3–8 20 free levels

Science · Discovery Coast

River Mystery

Something changed the river. Sample sites with a limited budget, follow the evidence and find where the change begins.

Play free See all levels
Grades
3–8
Levels
48 in 2 tracks
Free
20 levels
Session
5–15 minutes

What it is

People at the lake noticed the water has changed. Children choose which sites along the river to sample, each sample costing one from a small budget, and read a field notebook: clarity tube, water temperature, nitrate test strip and, later, critter counts. The goal is the first changed site, backed by clean evidence just upstream. Older levels add a joining stream, name every changed reading and leave no spare samples. Short questions cover the water cycle, watersheds and why some critters need clean water. All places, readings and critter counts are made up for the game.

What children learn

Planning an investigation with limited samples (sampling in the middle halves the stretch to search), using evidence for a conclusion (a changed site with a clean neighbor just upstream), water moving downstream through a watershed, the water cycle, and how clarity, temperature, nitrate and sensitive critters tell us about water quality.

What it teaches

  • Investigate and use evidence
  • Water on Earth
  • Habitats and needs

How to play

Tap a lettered site on the map (or Tab to the map and use the arrow keys, then Enter) and confirm to sample it. Readings appear in the notebook. In the report, choose where the change begins, the clean evidence upstream and what changed, then press Check. Reset investigation starts sampling again.

Plays with: Touch Mouse Keyboard Pen

Accessibility

  • Read-aloud on request
  • Fully playable with a keyboard
  • Calm mode with reduced motion
  • No timers or time pressure
  • Never relies on color alone
  • Quiet mode turns off sound effects

Level maps

Tracks and levels

Each track is made for a grade range. Start anywhere that fits — you don't have to play the younger tracks first. As a guest, your stars are saved on this device.

Clear Creek

One creek from spring to lake: soil, warm water or fertilizer, then critter counts, the water cycle, watersheds and two-reading changes. 3–5 24 levels · 10 free

Clear Creek

One creek from spring to lake: soil, warm water or fertilizer, then critter counts, the water cycle, watersheds and two-reading changes. · 3–5

Levels 1–10 free
  1. 1 Creek Walk 1 ☆☆☆
  2. 2 Creek Walk 2 ☆☆☆
  3. 3 Creek Walk 3 ☆☆☆
  4. 4 Creek Walk 4 ☆☆☆
  5. 5 Creek Walk 5 ☆☆☆
  6. 6 Creek Walk Challenge ☆☆☆
  7. 7 Critter Count 1 ☆☆☆
  8. 8 Critter Count 2 ☆☆☆
  9. 9 Critter Count 3 ☆☆☆
  10. 10 Critter Count 4 ☆☆☆
  11. 11 Critter Count 5 Plan level
  12. 12 Critter Count Challenge Plan level
  13. 13 Watershed Trail 1 Plan level
  14. 14 Watershed Trail 2 Plan level
  15. 15 Watershed Trail 3 Plan level
  16. 16 Watershed Trail 4 Plan level
  17. 17 Watershed Trail 5 Plan level
  18. 18 Watershed Trail Challenge Plan level
  19. 19 Double Clue 1 Plan level
  20. 20 Double Clue 2 Plan level
  21. 21 Double Clue 3 Plan level
  22. 22 Double Clue 4 Plan level
  23. 23 Double Clue 5 Plan level
  24. 24 Double Clue Challenge Plan level

Levels after 10 are part of a PlayOwl plan. Free levels, saving and basic reports stay free.

Start Clear Creek

Watershed Watch

A river with a joining stream: changes on either branch, every changed reading named and no spare samples. 6–8 24 levels · 10 free

Watershed Watch

A river with a joining stream: changes on either branch, every changed reading named and no spare samples. · 6–8

Levels 1–10 free
  1. 1 Two Streams 1 ☆☆☆
  2. 2 Two Streams 2 ☆☆☆
  3. 3 Two Streams 3 ☆☆☆
  4. 4 Two Streams 4 ☆☆☆
  5. 5 Two Streams 5 ☆☆☆
  6. 6 Two Streams Challenge ☆☆☆
  7. 7 Branch Hunt 1 ☆☆☆
  8. 8 Branch Hunt 2 ☆☆☆
  9. 9 Branch Hunt 3 ☆☆☆
  10. 10 Branch Hunt 4 ☆☆☆
  11. 11 Branch Hunt 5 Plan level
  12. 12 Branch Hunt Challenge Plan level
  13. 13 Every Clue 1 Plan level
  14. 14 Every Clue 2 Plan level
  15. 15 Every Clue 3 Plan level
  16. 16 Every Clue 4 Plan level
  17. 17 Every Clue 5 Plan level
  18. 18 Every Clue Challenge Plan level
  19. 19 Field Expert 1 Plan level
  20. 20 Field Expert 2 Plan level
  21. 21 Field Expert 3 Plan level
  22. 22 Field Expert 4 Plan level
  23. 23 Field Expert 5 Plan level
  24. 24 Field Expert Challenge Plan level

Levels after 10 are part of a PlayOwl plan. Free levels, saving and basic reports stay free.

Start Watershed Watch

Keep exploring

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