When a child is involved the adults need to be adults. This did not happen here. While it is easy to blame the school district in my experience most mothers do understand if something aobut their life or their family's life is a bit unusual. Why did the mom not read the handbook carefully and at least ask a question before sending her son to school? Does the school district have the children come to the registration or meet the children before the first day of school? My children visited the teacher for kindergarten before the first day, to learn the classroom and meet the teacher.
The child's view of school is something to see. Add to a rather unusual perspective the stress of new faces, new places and lots of excitement some advance thinking can keep the first day positive. Cultural challenges can be well managed with a bit of forethought. Folks, with children we do have to think ahead. That is what being an adult is all about.