OK, so here is a suggestion:
Wednesday: Travel from Grand Tetons to Canyon. You don't say when you are going, so can't guess on when it will get dark, but you need to be in Canyon by sundown. On the way, you if you have time, you can see West Thumb geyser, basin, stop at Fishing Bridge, park and walk across looking for wildlife, Mud Volcano, Hayden Valley, then you will get to Canyon. If you have time, try to do the Visitor Center and the ranger program Wed. evening.
Thursday: See the Canyon viewpoints today. Start with the South rim, especially Artist Point, which is the easiest to get to. It's a level walk out to the viewpoint. On the North rim, at least do the walk down to the Brink of the Upper Falls if your group is OK with hiking at this elevation. From Canyon, head north over Dunraven, stop at Tower Fall, then head toward Mammoth. I usually route people out to Lamar Valley, but with 9 of you, it will probably take some doing to get everyone in and out of the car and to bathroom breaks. See the Lower terraces at Mammoth. The best bathrooms are the ones by the gas station and the bus parking lot. Drive the upper terraces then head south toward Norris junction, then out to West Yellowstone. Overnight in West Yellowstone
Friday: Make this your geyser day. Enter the park. Keep your eyes peeled for bald eagle and trumpeter swan between the west gate and Madison Jct. Turn right at Madison, then after you cross the Gibbon River bridge, turn right in to the Firehole Canyon Dr. Rejoin the loop road. Head for Old Faithful and the Upper Geyser Basin. You will pass several geyser basins, but I recommend you pick these up on the way back to West Yellowstone this afternoon. At the Old Faithful area. Go to the Visitor Center first. Write downt the times for the predictable geysers on the brochure available at the desk (50cents). Try to work these in to your walk. Walk thru the geyser basin down to Morning Glory pool. (Pit toilet down here) I usually start by going behind Old Faithful to the left and do geyser hill, then the boardwalks down the geyser basin, coming back on the paved path. Try to get ice cream at the Old Faithful Inn. I usually take it to the 2nd floor deck overlooking the geyser basin. When you are finished, retrace your steps to West Yellowstone and take in Black Sand Basin, Biscuit Basin and Midway geyser basins as time and energy allow. Also do the Firehole Lake Dr and Fountain Paint Pots.
Saturday: Return to Jackson. Go either via Canyon or Old Faithful. Canyon will be a bit longer but will give you another shot at wildlife viewing in Hayden Valley.
PeachBelle will probably be along to post her link to the Top10.
Here is a link to sunset times. Print out the calendar for the time you will be there. You will want to be to your lodging by dark as travel is difficult with big black shapes walking down the middle of the road.