Most programming classes suffer from teaching everything in the abstract: isolated code. In contrast in real world programming there's usually an existing code

Most programming classes suffer from teaching everything in the abstract: isolated code. In contrast in real world programming there's usually an existing code base you're working on. Never tried this, but what if teaching was more like real world? Given an existing code base the students would have more context for why the code does what it does, and get a more holistic view of coding techniques.