Upload an EPUB. Evidence Based Vocabulary extracts the words your kid doesn't know and brings each one back exactly when they'd forget it — on the schedule the science of memory has recommended for a century.
One vocabulary card, under thirty seconds. Image, audio pronunciation, a sentence pulled from the chapter, four choices. Difficulty adjusts automatically.
A real exercise from a real chapter. Image generated per word, audio is real-speaker pronunciation, sentence lifted straight from the book your kid uploaded.
Most vocabulary apps run on a fixed schedule: roughly ten words a week, your kid takes a quiz on Friday, and those words never come back. The research on what happens next is unambiguous — about 80% of new vocabulary is gone within a week. That number has been replicated for over a century.
The proven alternative is spaced repetition. But the existing tools — Anki and its descendants — were largely designed for adults. They ask the learner to rate their own confidence ("Easy / Hard / Again"), tolerate steady failure while the algorithm calibrates, and read text-heavy cards. Most kids can't do any of those reliably. Evidence Based Vocabulary is spaced repetition rebuilt for the way kids actually learn.
Upload the EPUB they're reading — Hobbit, Narnia, Wings of Fire, whatever. Evidence Based Vocabulary extracts the words they're likely to stumble on and builds the review deck from there. No artificial weekly lists, no manual card creation.
No "Easy / Hard / Again" buttons. Every word's challenge stays in the 70–85% accuracy zone where retention is highest. Spelling difficulty progressively hides letters as the word is mastered; meaning difficulty graduates from same-context recognition to novel sentences to multi-sense discrimination. Both directions adapt automatically — your kid never self-assesses.
Every card has an image, an audio pronunciation, and IPA phonetics — seconds each, no walls of text. A short cooldown between cards prevents ghost-taps, and a calming break appears if your kid hits two wrongs in a row.
Make your kid want to come back tomorrow and learn a few more words from their book.
Everything in Evidence Based Vocabulary — the spaced repetition, the morpheme work, the difficulty smoothing, the seconds-each cards — is a closed loop in service of that one thing.
Our daughter read at a 4th-grade level by kindergarten. She'd already finished all of Harry Potter and most of Roald Dahl; she was deep into Narnia and had just polished off The Hobbit.
But we noticed something the research already says out loud: she'd skip past unknown words, or guess from context and quietly internalize the wrong meaning. Reading volume alone wasn't building deep word knowledge — and the vocabulary apps we tried were the same rigid ten-words-a-week treadmill we'd hit as kids ourselves.
So we built Evidence Based Vocabulary. It teaches her the words she's actually encountering, on a schedule the science of memory has been recommending for a hundred years. She retains far more from it than she ever did from the weekly-list apps we tried before — though that's a single-family observation until our beta data lands.
Built by a software engineer with 10+ years on ML systems at autonomous-vehicle and AI companies. Long-time Anki user. Building this in evenings and weekends, anonymously, for our own kid.
Every design decision in Evidence Based Vocabulary maps to a named research tradition. Not "AI-powered" or "research-backed" hand-waving — specific findings, applied directly.
| In the app | In the research |
|---|---|
| Daily review queue | Spaced repetition / spacing effect |
| Active recall quizzes, not flashcards | Retrieval practice (the testing effect) |
| An image generated for every word | Dual coding theory |
| Morpheme discovery (un-, -ness, root meanings) | Morphological awareness |
| Re-encounter and sense-extension cards | Depth of word knowledge; polysemy |
| Words pulled from books they're actually reading | Tier-2 vocabulary; reading-volume effects |
| Audio + IPA pronunciation on every card | Phonological-loop encoding |
| Smooth difficulty kept at 70–85% accuracy | Desirable difficulty |
$19.99 per month, per student, with a 14-day free trial. No credit card required to start. Cancel anytime — and your kid keeps using the app through the end of the period you've paid for.
Today. Sign up takes 30 seconds and your kid can start their first lesson within minutes.
$19.99/month per student, with a 14-day free trial. No credit card required to start. Cancel anytime, and your kid keeps using the app through the end of the period you've paid for.
Designed for independent readers — roughly ages 6 to 14. The adaptive difficulty means it works for a strong reader at age 6 and a struggling reader at age 14 alike. Younger kids who aren't reading independently yet won't get much from it.
Any modern web browser — phone, tablet, or laptop. No app to install. Optimized for tablets, where most kids prefer it.
Your kid plays through 'The Wind in the Willows' for 14 days — full vocabulary lessons, illustrations, the whole experience. We don't ask for a credit card up front; you only pay if you decide to keep going. Subscribe to upload your own books and unlock the full library.
The same way we handle our own daughter's: stored only in the account you control, never sold, never shared, never used to train third-party models. Full data export and deletion on request. See our privacy policy for details.
Two reasons. First, kids retain words far better when those words appear in something they care about — a Hobbit chapter beats an SAT list. Second, the research on Tier-2 vocabulary (Beck, McKeown, Kucan) finds that the highest-leverage words are the ones a child has just almost understood from context but not quite — exactly the ones their book hands you for free.
Spiritually yes — we're long-time Anki users ourselves. Practically no, in three specific ways. First, the deck builds itself from the EPUB your kid is reading; no manual card creation. Second, two adaptive tier systems run alongside SM-2 — a spelling tier that progressively masks letters as the word is mastered, and a usage tier that adds re-encounters in new contexts, novel-usage judgments, and sense-extension cards for words with multiple meanings. Third, morpheme work and image/audio/IPA come built in — in Anki you'd build all of that yourself.
Software engineer, 10+ years building ML systems at autonomous-vehicle and AI companies. Long-time Anki user. Built for our own daughter — who uses Evidence Based Vocabulary every day, as our future kids will. We dogfood what we ship.
14 days free, no credit card required. Cancel anytime.