How you respond to a pump varies from person to person as was said.
I would go into it positively though and not think you will need to supplement. I never supplemented my DD1 and I pumped.
I would pump on the way to work in the car as well from what you posted in your schedule. If you are afraid to pump and drive (a lot of moms do it). I would just try to pump in class as son as you get there before the kids come in.