ChasG
I feel your pain and a run of poor weather is just as frustrating for the Instructor. One of the challenges for instructors in your situation is dealing with skill/knowledge fade. It is very important to maintain what you have otherwise you get into the situation where after a bunch of cancelled flights, you finally get to go only to use most of the flight reviewing what you have allready done and hardly make any progress. My advice is if a flight is cancelled take a 1/2 hour or so and chair fly the last flight. By that I mean sit down and set out your maps, checklists, and instrument panel poster. Run through the flight from the inital walkaround to tie down at the end of the flight going through all the checks, radio calls, standard operating procedures, manoever sequences etc etc. This will keep the flying juices flowing and the info current. if during the chair flight an item comes up that you are unsure of, make a not of it and you can get it addressed at the next lesson.