I like to discuss my expectations and what I am going to try to teach them before every flight and review afterward. It take a bit more time but it's worth it IMO. Students seem to want to turn their planes upside down for some reason or want to fly off to the adjacent county. It can be hard getting through to some of them. You can tell them what manuever you want them to do for the first lessons and after a while let them tell you what THEY have planned and grade how well they execute it. ALWAYS have your recovery plan ready so it won't delay your response. And ALWAYS expect the wierdest things in the world so you won't be surprised too badly.[X(]