I think in my friend's case, the school district would prefer there were fewer ADD diagnosis. Allowing these kids all kinds of special privliges causes a lot of harm in the long run. It does no one any favors to put a child who will not behave and will not attempt to do work in a regular or even honors classroom. The worst aspect of it all is the truancy issue. Some of these "disabled" students just can't stay in school the whole day, they must either come in late or leave early - without permission. If the school tires to discipline a student for all these unexcused absences, the parents threaten to sue - after all, the poor child is disabled, so he can't be expected to show up at eight each morning like everyone else. It puts the school in a horrible bind because when a student is truant, the school is still liable for his or her safety. If a student cuts out early and then gets, say, hit by a car, the parents can - and will - sue the school district to kingdom come. So the school is damned if they do and damned if they don't.
I no longer teach chemistry in High School. It is impossible and dangerous to teach this subject with seven special education students and no assistant-every lesson plan and lab must be altered in order to compensate for eight different types of learning. Lab is just plain scary. At my last school, some of these kids broke into the lab and killed some of the animals.
Also, during my school days in Florida, it was known as RBATTB (Rather Be At The Beach) syndrome. Don't ask how I know...