I had a similar problem with my son when he was in pre-school/K.
Not only did he have long bus rides but he would often get to school 10-15 minutes after the bell rang and would leave early. I got a letter from his doctor stating that it was medically harmful for him to remain in his wheelchair /one position more than 45 minutes because of his CP. It had a nice boomerang effect of making the classroom aides get him out of his chair through out the day as well. I also threaten to file an civil rights complaint in regards to the late drop off /early pick up because he was being denied the same amount of educational time as his typical peers simply because he was disabled.
Joanne