The Path of a River
Like Duolingo, but for The Path of a River. Tomo turns the whole topic into a game you play five minutes a day, until it actually sticks.
For the part of you with thirty open tabs that never became anything.
Free forever · No credit card · iPhone & Android

Key ideas in The Path of a River
- Rivers always seek the lowest possible elevation
- Water gains momentum on the outside of a curve
- Water flows around obstacles rather than through them if the path is easier
- Fast-moving water has enough energy to scour and carry away soil
- Gravity pulls water toward the sea via the path of least resistance
- Erosion happens where the current hits the bank most directly
- How gravity and terrain dictate a river's path
- The relationship between water speed and bank erosion
- Slowing water loses the energy needed to carry sediment
- The inside of a bend is a 'dead zone' where speed drops
- Deposited material builds up land on the inner bank
- Straight paths cause water to speed up to dangerous, destructive levels
- Curves create friction that helps the river bleed off excess energy
- Meandering is a natural way for the river to maintain a steady, manageable pace
- How water speed creates different river features
- The purpose of a river's winding shape
You've tried the other tabs
Thirty open tabs. Four facts you actually kept.
You watched. You nodded. By Sunday it was gone.
One answer, then back to scrolling.
Eight weeks. You meant to finish. You didn't.
Tomo gives The Path of a River the Duolingo treatment: levels, streaks, and quick quizzes that test what you just learned. That game loop is what the tabs above never had, so it's the one you actually finish.
Here's what playing it feels like
A real question from this course. Take your best guess.
When a river hits a bend, where does the water reach its highest speed?
Get it right to open this lesson and 8 more in the app.
Where The Path of a River takes you
Follow the journey of water from mountain peaks to the open sea. Learn to read the landscape and understand how moving water carves the world around us.
- 1
Following the Flow
- Reading the River's Curves
- The Journey from Source to Sea
- 2
The River's Power
- How Rivers Redraw the Map
2 sections · 3 units · 9 levels. Built to play, not to enroll.
You pick the voice
The Path of a River is taught in the The Professor style: clear, structured, thorough. Want a different feel? In the app you can spin up the same topic in any of Tomo's teaching styles. Same facts, totally different vibe.
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Start The Path of a River today.
Download Tomo, search The Path of a River, and play your first lesson in under a minute.