Privacy Policy
Last updated: July 2026
1. Information You Provide
When you enroll, create an account, contact us, or use our programs, we collect:
- Name and contact details (email, phone number; optionally WeChat or Discord ID)
- Student information (grade level, school name, state, competition history and goals)
- Parent/guardian name and contact details
- Payment information, which is entered on and processed by Stripe — we do not store full card or bank-account numbers
- Academic records generated within our programs (homework, test scores, progress notes)
- Messages you send us through the contact form or the site chat assistant
2. Information Collected Automatically
When you use our website and portal, we and our providers automatically collect:
- Device and connection data, including IP address and browser/user-agent, used for security, abuse prevention (rate limiting), and troubleshooting
- Usage and analytics data via Google Analytics (GA4), including pages viewed and general interactions, to understand and improve the site
- Email engagement data for our newsletter, including whether a message was opened (via a tracking pixel) and which links were clicked
- Class attendance and recording-access data when you join sessions through our Zoom integration
- Cookies and similar technologies (see Section 5)
3. How We Use Your Information
- Provide, maintain, and improve our educational services and website
- Process payments and send enrollment, receipt, and administrative communications
- Create and manage class access, including Zoom sessions and Google Classroom rosters and materials
- Track attendance, homework, and progress, and provide personalized feedback
- Send program updates and, where you have subscribed, newsletters (you can unsubscribe at any time)
- Secure our services, prevent abuse, and comply with legal obligations
- Respond to inquiries and provide support
4. Third-Party Services We Share Data With
We do not sell or rent personal information. We share it only with service providers that help us operate, each acting under their own privacy terms:
- Stripe — payment processing
- Google — sign-in (OAuth), Google Classroom (class materials/rosters), and Google Analytics (site analytics)
- Zoom — live classes, attendance tracking, and cloud recordings
- Resend — transactional and newsletter email delivery
- Supabase and Vercel — database hosting and website hosting/infrastructure
- Others when required by law, or to establish, exercise, or defend legal rights
5. Cookies & Analytics
We use cookies and similar technologies for two purposes: strictly necessary cookies that keep you signed in and secure your session, and analytics cookies set by Google Analytics to measure site usage. You can control cookies through your browser settings and can opt out of Google Analytics using Google's browser add-on. Blocking strictly necessary cookies may prevent you from logging in.
6. Children's Privacy
Our programs serve students who are often minors. We collect student information in the context of an educational service and expect a parent or guardian to be involved in enrollment and to consent to our collection and use of their child's information. If you are a parent or guardian and wish to review, correct, or delete your child's information, contact us at chen@dcho.us.
7. Data Retention
We retain personal information for as long as your account is active and as needed to provide our services, then for a reasonable period afterward to meet legal, accounting, and record-keeping obligations. We delete or anonymize information when it is no longer needed, subject to those requirements. You may request deletion at any time (see Section 8).
8. Your Rights
You may request access to, correction of, or deletion of your personal information, and you may unsubscribe from newsletters at any time via the link in each email or by contacting us. To exercise any of these rights, email chen@dcho.us.
9. Changes to This Policy
We may update this Privacy Policy from time to time. When we do, we will revise the "Last updated" date above.
10. Contact Us
If you have questions about this Privacy Policy, please contact us at:
Email: chen@dcho.us
WeChat: chenq236