Our problem was, our little morning class didn't know the envelope drill. Soooo, we've been breaking it down into bite-size chunks and practicing those. It's actually opened a few doors to other little "sub drills" if you will that I think are kind of fun. Here's one we worked on this morning:
1) Begin as you would with the regular envelope drill: uke lying on his back and tori in kuzure kesa gatame.
2) Uke rolls toward tori, who then transitions into mune gatame.
3) Uke rolls away from tori, and tori transitions back to his own side, this time facing uke's feet in ushiro kesa gatame.
4) Now, uke rolls toward tori again, but instead of moving on to the next part of the "envelope drill" (which would be kuzure kame shiho gatame) he transitions back into mune gatame.
5) Uke rolls away from tori, and tori transitions back to kuzure kesa gatame.
So, basically, we're taking the first three positions of the "envelope drill" and having each partner repeating them back and forth several times, both sides.
1) Proceed through the first three steps from above, moving from kuzure kesa gatame to mune gatame to ushiro gatame.
2) This time, when uke rolls toward tori, tori reaches to the far side of uke's knees (so if tori is working on uke's right side, tori will reach over to uke's left knee) and pulls uke's knees towards himself. Tori can then step over with his right leg into tate shiho gatame.
3) Now, it's uke's turn to drive the bus. His job is to do the standard escape, which in turn allows him to roll his partner over and for him to hold tate shiho gatame.
4) From there, uke (who, I guess, is actually tori at this point, but I don't want to confuse you...) "swims" one arm over so that both of his arms are on the same side of his partner's head, moving clockwise (it would be counter-clockwise, of course, if you started on uke's left side). Uke swings his right foot over and back until he's sitting in ushiro kesa gatame.
5) From there, the roles continue to be reversed, so tori is now on his back and rolling toward uke, who then transitions to mune gatame.
6) Tori rolls away and uke transitions to kuzure kesa gatame, and guess what? We're back to the beginning of the drill—but you've switched roles, so just keep going! Be sure to work both sides, though.
1) Start as you have in the previous drills, with tori in kuzure kesa gatame.
2) In this version, uke should be keeping his elbows in, his hands close to face in the classic defensive position (if he hasn't been doing this already). When he rolls toward tori, tori will switch to his stomach as he would normally do for mune gatame, but—presuming tori started on his right side—uses his left hand to catch uke's left wrist. This will create an immediate torque on uke's elbow and shoulder that will make him really, really want to roll to his back again.
3) As he does, tori remains flat (stomach down) and proceeds to snag an ude-garami, or coil arm bar, or "Americana."
There's probably more one could do in this area, but hey, class only lasts so long! I have a few other drills for the other sections of the envelope drill, and hopefully I'll get around to posting them.