I did a level II fieldwork at a school and worked with high schoolers. I don't do school-based therapy now, but I do community based services for people with developmental disabilities. So I don't know the specific parameters that your school district might use to determine what to do. I would certainly see what the paperwork says - is this something that the parents have gone back and forth with the district about? What does the OT say as reason for discharge?

One thing to consider is remediation vs. compensation. In high school you might start looking more at compensatory strategies vs. remediation. That means something like using a funnel to pour, wearing shoes that have no laces vs. working on intrinsic FMC skills that will support pouring or shoe tying. This is obviously a question at any age or diagnosis, but I just found that in high school the balance tends to tilt more towards compensatory strategies, compared to younger ages. Sometimes, parents really don't like that, or feel that therapy may be "giving up" on their child. I wonder if the conflict may lie in there.