1) There is an entire professional apparatus that is in charge of knowing what a) the student has b) what is necessary to deal with a students' issues and potential outbursts.
2) in no way are the parents legally responsible to provide the school with the equipment necessary for that student's academic experience when it comes to the special need. The responsibility falls to the state and it's various outlets (the school, vocational rehabilitation, etc.)
3) That IEP team is supposed to have qualified staff that are able to professionally and ethically serve the student. Mom and Dad are not expected to be psychologists, physical or speech therapists. That is the team's job.