Frequently asked questions
Answers to the questions parents ask us most often. If yours isn't here, email hello@evidencebasedvocabulary.com — we read every message and usually reply the same day.
What is Evidence Based Vocabulary? Who is it for?
Evidence Based Vocabulary is an AI-tutored vocabulary app built around the books your kid is already reading. You upload an EPUB, the app extracts the words your kid is likely to stumble on, and brings each one back on a spaced-repetition schedule designed to maximize retention. It's designed for independent readers, roughly ages 6 to 14 — the adaptive difficulty means a strong reader at 6 and a struggling reader at 14 both get cards calibrated to them.
How does the AI tutoring work?
For every vocabulary word, an AI model generates a kid-appropriate definition, a custom illustration, audio pronunciation lookup, and a quiz pulled from the actual sentence in the book your kid uploaded. As your kid progresses, the app tracks accuracy and response time per word, and uses the SM-2 spaced-repetition algorithm to schedule each word's next review — typically the day before it would otherwise be forgotten.
The "tutoring" part is the adaptive layer on top: a spelling tier that progressively masks letters as the word is mastered, a usage tier that introduces re-encounters in new contexts and discrimination cards for polysemous words, and a morpheme-discovery track that teaches productive prefixes and suffixes (un-, -ness, re-) so future unfamiliar words start to decode themselves.
What data do you collect about my child?
The minimum necessary: a first name (or pseudonym — your choice), age or grade level, reading level, the books you upload, and your kid's quiz responses (which words they've seen, what they got right or wrong, how long it took). We do not collect your child's last name, address, phone number, email, photographs, audio, or precise location. We do not run advertising trackers, and we do not share or sell your child's data. Read the full privacy policy for details.
Is it safe? What about inappropriate content?
The app is COPPA-compliant and was designed from the start for kids. There's no chat, no social features, no way for anyone outside your household to contact your child. The AI-generated content (definitions, illustrations, example sentences) goes through age-appropriate prompt engineering and safety filters, and is regenerated anytime we get a parent flag. Words extracted from books are filtered for child-appropriateness before they ever reach the deck.
Can I review what my kid is doing?
Yes — that's a primary feature, not an afterthought. The parent dashboard shows progress charts, session history, mastery forecasts, and a per-word breakdown of where your kid is on the spelling and usage tiers. There's also a live spectator mode where you can watch the session as it's happening — the cards, the answers, the hesitations — without your kid seeing anything different on their screen.
Can I use it on a phone?
Yes — the app runs in any modern web browser, no install required. That said, we've designed and tested most heavily on tablets (the kid-facing layout looks best at tablet sizes), and the parent dashboard is currently optimized for laptop and tablet. Phones work but the layout is tighter; we are actively improving the small-screen experience.
Can my kid use it offline?
No — Evidence Based Vocabulary needs an internet connection. The AI generation, spaced-repetition scheduling, and progress sync all happen on our servers. We've optimized for low bandwidth and pre-fetch the next chapter's images during idle time, so it works fine on slow connections, but it doesn't run fully offline.
How long are the lessons?
Sessions are designed to be roughly 5 to 10 minutes — short on purpose, because the research on the peak-end rule says a kid will remember a session as fun if it ends before fatigue sets in. The app caps new words per session (default 3, adjustable in parent preferences) and times each session toward a target active-engagement budget. Most kids do one session per day; the algorithm is built around that cadence.
What books are supported?
English-language books in EPUB or plain text (.txt) format. During the free trial, only "The Wind in the Willows" is available — that's enough to evaluate the full product without uploading anything yourself. Once you subscribe, you can upload any English EPUB or .txt file you legally have the right to use (a book you bought, a Project Gutenberg title, etc.). We do not currently support PDFs or non-English titles.
What happens after my free trial?
The 14-day trial ends and your kid's access pauses until you subscribe. Subscribing is $19.99/month per student, billed through Stripe; we never see your full card number. Your kid's progress, history, and uploaded books are preserved through the conversion — they pick up exactly where they left off. If you don't subscribe, your data is held under our soft-delete grace policy (see the privacy policy) before being permanently deleted.
Can I cancel anytime?
Yes. You can cancel through the Customer Portal in your parent dashboard, or by emailing us. Cancellation stops future charges immediately, and you keep full access through the end of the period you have already paid for. The first 7 days after your first paid charge are no-questions-asked refundable — full details in our refund policy.
How do I contact support?
Email hello@evidencebasedvocabulary.com. We read every message — it's a small team — and usually reply within one business day. For billing questions, please contact us before filing a chargeback with your bank; in nearly every case we can resolve the issue directly and faster.
Still curious? Try the 14-day free trial — no credit card required.
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