> Then ask harder questions that show the value of the harder (more complicated, less intuitive) methods. It's not clear to me that there's an obvious right an

> Then ask harder questions that show the value of the harder (more complicated, less intuitive) methods. It's not clear to me that there's an obvious right answer here, but I do believe that most obvious answers are, to some degree, wrong. Namely, saying "just ask harder questions" doesn't take into account that then the student is trying to solve hard questions and learn a new method at the same time. Teaching a more general method on easy problems gives time to become acclimatised to the method, while also offering sanity checks (by easier, faster, and / or approximate methods) to make sure that it's not going wrong. On the other hand, as you say, this approach seems unmotivated, and bores or frustrates students—there's no obvious right answer! I think that all that can be said is that one must find the appropriate balance for each individual student, or class.