I am most impressed with the advice of the Julia Robinson Mathematics Festival to the volunteers who come to people its tables:
Be as unhelpful as possible.
This is marvellous advice for educators and parents to follow most of the time. As a parent I struggle with keeping it. Too often I jump in and offer short-term “help” to avoid frustration. In an elementary school classroom I am much more successful… faking ignorance, commiserating at how tough it is and purposely offering wrong advice. Students learn that they really can’t rely on me to solve much of anything. I maintain this ruse until it is time to highlight some mathematical structure (hopefully discovered by a student) when my perceived ability temporarily rises 😉
For older students – who will not be fooled by this routine there is a solution: Be unprepared! Enter the classroom without knowing the solution to the tough problem that you are about to set them to work on. This will liberate you. It might be nerve-racking at first, so feel free to fake it the first time… but I guarantee that many students will get motivated when they realize their teacher doesn’t know the answer.