Big Numbers: Reading and Writing
Like Duolingo, but for Big Numbers: Reading and Writing. 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.
A short one: 12 levels across 2 sections, about 24 minutes end to end, roughly 5 days at five minutes a day. It moves through The Architecture of Numbers and Mastering the Scale. It starts from scratch.
Free forever · No credit card · iPhone & Android
Key ideas in Big Numbers: Reading and Writing
- A digit's value is determined by its position in a number
- Commas separate groups of three digits called periods
- Moving one seat to the left makes a digit ten times larger
- The first comma from the right marks the start of the thousands neighborhood
- The digit 4 can represent 40, 400, or 4,000 depending on its seat
- You say the neighborhood name only when you reach the comma
- How the same digit changes value based on its position
- Using commas as cues for naming periods
- Every group of three digits follows the Hundreds-Tens-Ones sequence
- The middle digit of any three-digit group always represents 'tens'
- Read the three digits before the comma as if they were a standalone number
- Attach the period name (thousand) at the comma
- Recognizing the repeating H-T-O pattern across different periods
- The role of zero in maintaining place value alignment
- Reading large numbers by breaking them into three-digit chunks
- Standard form uses digits (0-9) to represent values compactly
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 Big Numbers: Reading and Writing 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.
What do we call the groups of three digits separated by commas in a large number?
Get it right to open this lesson and 11 more in the app.
Where Big Numbers: Reading and Writing takes you
Master the architecture of large numbers. Learn to read, write, and compare values up to one million using the power of place value.
- 1
The Architecture of Numbers
- The Place Value Neighborhood
- The Three Languages of Numbers
- 2
Mastering the Scale
- The Power of Ten
- Rounding to the Nearest Landmark
2 sections · 4 units · 12 levels. Built to play, not to enroll.
You pick the voice
Big Numbers: Reading and Writing 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 Big Numbers: Reading and Writing today.
Download Tomo, search Big Numbers: Reading and Writing, and play your first lesson in under a minute.