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 child is reading or about to read. It turns real passages into short daily practice, then brings each word back on a spaced-repetition schedule. 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 app teach each word?
For every vocabulary word, the app creates a kid-appropriate definition, a custom illustration, audio pronunciation lookup, and a quiz pulled from the actual sentence in the book your child uploaded. As your child 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 adaptive layer adds 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.
How do you choose the words?
We start with the books your child is reading, then prioritize words that matter beyond one page: words that appear often, show up across many kinds of English, and fit the learner's likely level. That means practice is tied to real reading while still building vocabulary for clearer communication, stronger comprehension, and sharper critical thinking.
Can I review what my child 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 child 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 child seeing anything different on their screen.
How long are the lessons?
Sessions are designed to be short on purpose, usually around 5 to 10 minutes. The app caps new words per session, parents can adjust the limit, and the algorithm is built around a small amount of focused daily practice instead of long sessions that lead to burnout.
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 child's access pauses until you subscribe. Subscribing is $19.99/month per student, billed through Stripe; we never see your full card number. Your child'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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