This article reminds readers of the benefits that use cases bring to the software development process. Use cases, as featured in the UML (Unified Modeling Language), are contrasted with the much terser "user stories" favoured by agile methods. With their normal and alternative flows, and extending and included behaviours, use cases encourage developers to consider actor-system interaction in detail, preparing the way for coherent mechanisms of interacting and inheriting objects that realise the required functionality. The textual and visual representation of use cases has a simplicity that encourages discussion of requirements among developers, and between developers and clients, but only if "use case basics" are understood and applied consistently. An innovative use of educational software is proposed, to alleviate some fundamental but recurring difficulties, and to give students in large cohorts the benefit of focussed tuition and feedback. The approach will appeal to educators in software engineering and beyond.