Frequently asked questions

Use Join for free in the navigation. You need a working email address, and you will be asked to confirm it before you start.

Choose Forgot password on the sign-in page. We will email a reset link to the address on your account.

Yes. Ask through the contact form and choose General. Deletion is permanent and cannot be undone.

Maths, the sciences, computer science, history, writing, philosophy, psychology, engineering, art and music, for grades 6 to 12 and introductory college, across 14 dedicated AI tutors.

Yes. Seven days of Core, no credit card required, with full access to everything.

Core and Pro subscribers can download content for offline study. Your progress syncs automatically when you reconnect.

Progress saves to your account as you work, so you can stop mid-lesson and pick the same place up on another device.

Card payments, handled by Stripe. We do not take PayPal.

From your subscription page, which opens the Stripe billing portal. You can switch plan or cancel there.

Ask through the contact form with your account email and what you paid for, and we will look at it.

Refresh first, then try a different browser or a private window, which rules out a stale cache or an extension. If it survives that, tell us through the contact form and say which browser you were on.

Through the contact form, choosing General. What we need is the page you were on, what you expected, what happened instead, and a screenshot if you have one.

Not yet. SFTS runs in a phone or tablet browser today, and a native app is in development.