How lesson bundles are billed

Many tutors sell lessons in bundles — pay for eight, teach them down. In memore a bundle is not a special object; it is simply credit on the student's balance, spent by classes as they complete.

The flow

1. The student pays for the bundle; you confirm the payment (or log it yourself). Their balance now holds the money.
2. Each class bills when it completes — never when it is scheduled. Completing posts the class's price against the balance.
3. While credit remains, completed classes read as paid automatically. When it runs out, classes start showing unpaid, which is your cue to invoice the next bundle.

Reading the numbers

• A student's profile shows the balance and how many classes it still covers at their current price.
• The calendar's colours reflect the same arithmetic — a completed class only flags unpaid when nothing covers it.
• Balances are kept per currency. If you charge one student in euros and another in dollars, the two never mix.

Refunds and corrections

Because the ledger is append-only, corrections are new entries, not edits — an adjustment or refund posts alongside the history rather than rewriting it. Your books always show what happened, in order, which is precisely what you want when a parent asks.