Privacy Policy

Quantametron is a math tutor for kids in Grades 4–8, currently in invite-only private preview. “We,” “us,” and “Quantametron” refer to the operator of this service. This policy explains what we collect, how we use it, and the rights a parent or legal guardian has over their child's data.

Quantametron is for parents or legal guardians and their children in Grades 4–8. Kids don't sign up. A parent creates the account, defines kid profiles, and supervises use. Kids then use the parent's signed-in session on a shared family device.

Because Grades 4–5 are typically ages 9–10, we know some of our users are under 13. We treat this as a service subject to the Children's Online Privacy Protection Act (COPPA) and similar state laws.

From the parent:

• Email address and password (for parent sign-in)
• A parent PIN (to unlock the parent admin area)
• A household display name

About each kid (entered by the parent):

• Display name
• School grade (4–8) and optional accelerated “math grade”
• Optional “About me” note — hobbies or interests you'd like the tutor to reference

From the kid as they use the tutor:

• Math questions they type
• Answers they give to the tutor's questions
• Which steps they expand, which hints they use
• Issue reports (“this question is confusing”) they file

Automatically collected (standard for any web service):

• Timestamps of sessions and questions
• IP address (for rate-limiting and abuse prevention only)
• Browser user-agent (for diagnostic logging)

We do notcollect the kid's real name, school, location beyond timezone, photos, voice recordings, contacts, or anything not listed above.

• To run the math tutor: questions and grade are sent to our AI provider (Anthropic, see “Who else sees it” below) to generate explanations.
• To show a parent's dashboard: progress, topics mastered, recent questions and wrong answers.
• To send you a nightly email digest of your kid's activity.
• To send transactional email (invites, password and PIN reset codes, waitlist confirmation).
• To prevent abuse (rate-limits keyed to IP and user account).

We don't show ads to kids. We don't sell personal data. We don'tuse kid data to train general AI models. We don't profile kids for anything outside the tutor.

We use a small number of third-party services to run Quantametron. Each receives only the data it needs to do its job:

• Anthropic(Claude AI) — receives each math question, the kid's grade, and the optional “About me” note. Anthropic's privacy terms apply.
• Resend — receives recipient email addresses and the content of emails we send (digests, invites, resets).
• Supabase — hosts our database and handles parent authentication.
• Vercel — hosts the application.

None of these providers are permitted to use your data for their own purposes beyond delivering the service to us.

• Kid-typed math questions: 60 days, then the text is scrubbed (the aggregate — which grade, how many attempts, what topic — is kept).
• Kid-typed answers: 60 days, then scrubbed.
• Saved questions (“My questions” list): 60 days, then the row is deleted.
• Shadow-judge comparison log: 30 days, then deleted.
• Aggregate progress (topics solved, attempt counts, time-series): kept as long as the kid's profile exists.
• Parent sign-in data: kept as long as the account exists. Delete the account and it's wiped.

Anything you delete via the parent dashboard (see below) is removed within 7 days.

Before we scrub the 60-day content described above, we copy certain pedagogically useful items — wrong answers, detected misconception patterns, and free-form math questions — into a separate de-identified corpus. These copies do not contain your child's name, your household, your email, a user ID, or any link back to your family. They record only: the typed text (wrong answer or question), the topic or catalog question, the misconception label, and the original timestamp.

We use this corpus to improve the tutor's explanations and grow our library of common misconceptions — the same way a teacher might notice “a lot of kids trip on this step” and adjust their lesson, without needing to know which kid. Because the corpus is de-identified at copy time, deleting your account or your child's profile does not delete these anonymous examples, but they can't be traced back to you.

You can, at any time:

• Reviewyour kid's data — in the parent admin area or via the data export tool.
• Correct any data — edit your kid's profile directly.
• Deleteyour kid's data — remove a single kid or the whole household from Settings.
• Refuse further collection — close the account.
• Export your kid's data as JSON — from Settings.

If you can't sign in or need help, email privacy@quantametron.com and we'll respond within 30 days.

Passwords and parent PINs are bcrypt-hashed. Sessions are cookie-based and expire. Our database is hosted in a Supabase project with row-level security enabled. We use HTTPS everywhere.

We're a small preview. We don't claim military-grade security. If you have a security concern, email privacy@quantametron.com.

• We collect the minimum information needed to run the tutor.
• We don't condition participation on providing more than is needed.
• We obtain parental consent at signup (a required checkbox) and again through the email-based invite process — a parent must own the email the invite was sent to.
• We do not link children's data across services, send them behavioral advertising, or enable them to make anything public.
• Parents can review and delete their child's data at any time.

If we materially change this policy we'll bump the version and ask you to re-accept next time you sign in. Non-material changes will post with a new version stamp but won't require re-acceptance.

For any privacy question, data access request, or concern: privacy@quantametron.com.