Swait,
I have used the following progression with good results.
Start on some easier terrain, greens or maybe easier blue runs. At the top of the trail in some flat area have them strap in with both feet and get balanced over the board and slowly start to shift thier wieght(Pressure)from center (balanced, stacked over your board) towards the tail of the board and then back to center. Think of the way you would start an ollie but do not load up the tail and pop. Just go from center to tail and back to center. This exercise is to get the rider to get the feeling of 2 things, 1) Distributing the pressure fore and aft or centered to tail (This is the what) and 2) Using independant flexion and extion of the front leg and the back leg (this is the how). When shifting, slidind the board from the centered balanced position you must extend/straighten your front leg and flex/collaps your back leg. Let them play with for a few minutes to get the concept and feeling down. Although at this point you are using a flat board the same concept will be applied while on an edge.
Making traverses across the hill set up the task to do this fore and aft presuure move 2 or 3 times while traversing across the trail on both toe and heel edges. This introduces the move while edging. Try to pick a wider trail if possible and the easier green or blue terrain will allow them not to build up to much speed. Have them initiate the turns by twist with thier front foot and once the board starts to cross the fall line create equal pressure along the entire edge by using your back foot to evenly distribute the pressure under your feet.Have them play with this until they seem comfortable with the move.
Set up the next task to make medium radious turns and put the 2 previous tasks together with with the focus in this task to finish the turns as the board crosses the fall line with the fore and aft pressure move. By finishing the turn with this move with pressure on the tail end of the board at the end of the turn and this becomes your speed control. Have them play with different turn shapes and vary how much to bring the board accross the fall line or even slightly uphill to see the effect on speed control this has.
Slowly increase the terrain pitch as the student becomes more comfortable with the move and take it to the steeps.
This thread has many ideas and no idea is better than any other idea. I look at it more as one concept can be more efficient or less efficient than another depending on the terrain and conditions. This concept focuses on pressure (Board performance) both fore and aft, down (decamber) and up (unwieght) and flex/extend of the ankles and knees (body movement)
I would recommend no matter what you try do it yourself and make sure you own it before you teach it.
Pat