How do I create a fee structure and generate invoices for a term?

Go to Finance → Fee Structures → New. Pick the academic year and term, choose the target classes, and add lines (fee item + amount + optional class/section/boarding/individual-student targeting). Save it as draft while you're still editing — only active structures can generate invoices, and only draft structures can still be edited. Once you're happy with it, activate it, then use Generate Invoices with an issue date and due date. Every enrolled student who matches the structure's lines gets one invoice automatically.