Mastering English Spelling
Like Duolingo, but for Mastering English Spelling. 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.
54 levels across 4 sections, about 108 minutes end to end, roughly 22 days at five minutes a day. It moves through Fixing Common Confusion, Decoding Complex Word Structures, Spelling for Professional Clarity, and The Logic Behind the Chaos. It assumes you already know the basics.
Free forever · No credit card · iPhone & Android

Key ideas in Mastering English Spelling
- A single consonant allows the vowel to say its own name (long sound)
- Doubling only happens when the final beat of the word is stressed
- Double consonants act as a wall to keep the vowel sound short
- Words ending in a weak beat like 'open' do not get a double letter
- How doubling a consonant preserves the short vowel sound
- The relationship between word rhythm (stress) and doubling consonants
- One consonant after a vowel usually signals a long vowel sound
- Two consonants after a vowel usually signal a short vowel sound
- Check if the word has one short vowel followed by one consonant
- Double the final letter to protect that short vowel sound
- Add the ending like -ed or -ing
- Predicting the vowel sound based on the consonant count
- The decision process for doubling a letter in a single-beat word
- Only words with a single vowel before the consonant get a double letter
- Vowel teams like 'oa' or 'ee' already protect the sound and don't need a double
- Identifying which words require a double letter based on their pattern
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 Mastering English Spelling 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 deciding to double a consonant in a multi-beat word, what must be true about the final syllable?
Get it right to open this lesson and 53 more in the app.
Where Mastering English Spelling takes you
Move beyond basic phonics to master the tricky patterns and silent letters that make English unique. Learn to predict spelling based on word origins and structural logic rather than just memorization.
- 1
Fixing Common Confusion
- Doubling Letters: When to Add an Extra Consonant
- The 'I' and 'E' Rule and Its Real Exceptions
- Words That Sound Alike but Look Different
- Handling the Silent 'E' When Adding Endings
- 2
Decoding Complex Word Structures
- Prefixes That Change Their Last Letter
- Suffixes for Nouns: 'Tion' vs 'Sion'
- The Mystery of Silent Letters in the Middle of Words
- Plurals for Words Ending in 'O' and 'Y'
- Compound Words: To Join or to Hyphenate
- Soft and Hard Sounds for 'C' and 'G'
- 3
Spelling for Professional Clarity
- British vs American Spelling Patterns
- Spelling Numbers and Fractions Correcty
- Commonly Misspelled Academic and Business Terms
- 4
The Logic Behind the Chaos
- How Latin and Greek Roots Guide Your Spelling
- French Influence: Why Some Words Have Extra Vowels
- Tracing Word History to Explain Weird Spellings
- The Role of Stress and Emphasis on Vowel Choice
- Predicting Spelling Through Word Families
4 sections · 18 units · 54 levels. Built to play, not to enroll.
You pick the voice
Mastering English Spelling 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 Mastering English Spelling today.
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