there are plenty of private and catholic schools in the USA that offer support services to kids with learning disabilities. and i believe it's something that they're working on now at SCS (at least as far as learning disabilities, maybe not speech and behavior) and they hired someone to take over that end in their high school. however, it's not enough.
there are some special schools for kids with severe problems - here in santiago, there's one in los jardines, that works with kids with behavioral disorders, adhd, dyslexia etc... BUT the "problems" are so diverse, I imagine it must be difficult for the teachers to work that out. and it's expensive (6,000 pesos a month) for most parents.
the public system has "escuelas especiales" but they mostly cater to downs syndrome and other kind of developmental issues, not necessarily learning differences. there's also the "sordo-mudos" (and why be PC? that's what the disability is - should we call them hearing and speaking impaired? that doesn't describe who the school works with as an impairment doesn't denote complete deafness.)
About seven years ago the government mandated that schools need to mainstream (integrate) visually impaired (not blind) children into classrooms with their peers. In the public system, they must be admitted (with teachers who have no training for that at all) but in the private system, it is up to the director whether or not to admit - i've seen few in my time here actually integrated into the classroom, but many who are sat a desk and ignored all day while the school collects their money.