Take a multimedia corpus, arrange the material for delivery via Spaced Repetition Learning (SRS) coupled with an active reinforcement learning system to gradually introduce and deepen understanding of topics that expand the learner’s challenge boundary.
Instead of teachers and fixed class sizes, allow students to self select into rooms based on noise level. Include a range of furniture from desks to couches. Any adults are only present to monitor for fighting or harassment and need no special training — they are certainly not to be responsible for lecturing or grading. Leave that to the machines. Perhaps direct students that have mastered material help students that have not.
Naturally and smoothly steer learners into vocational or academic studies based on their performance without social discontinuities like the German method.
One challenge with this approach would be how to organize appraisals of essays or long-form written content. Peer review might be one answer. There are, no doubt, many other challenges and criticisms. This scheme would dramatically upend the economics of education and make a large number of positions redundant.
The more evaluation and feedback are in the process, the more individualized it gets, the more burdensome and expensive it gets, generally. That's not to say we can't improve our teaching methods to automate some mechanisms for feedback and pace adjustment in the future, though...
Education is due for a genuine upset. I think there are a bunch of ways technology could make general education significantly more effective, given the technology was designed for that. (Current device / OS / app design norms are mostly in service of consumerism, which assumes no one ever wants to learn anything unless someone paid for them to hear it. So, not that stuff.)