Students with Special Needs...
Autism:
In the past I have worked with a student with Autism, Echolalia, bilingualism, and Sensory Processing Disorder. This made language acquisition very difficult for many many reasons. However, I will focus on the Autism and the issues he had due to that.
Autistic children have an extremely hard time processing words even if they are familiar with their meaning. Autistic students think in pictures not in words, so it is increasingly important to communicate in pictures rather than words. It is said that when you talk to an Autistic child in long sentences they only have the mental capacity to keep a few in their head for a short period of time. It is like building a long line of dominoes and eventually they just start falling off the table. In some situations words are completely lost and do not register.
With that in mind, it is extremely difficult to establish morphology, fluency, a strong vocabulary, comprehension, composition, and many other aspects of literacy.
These concepts of literacy can be achieved through pictures. The best way to communicate and have Autistic children to communicate their thoughts is through pictures. Frequently, aids establish a binder of pictures for Autistic students to form semi-sentences for communication. They may never understand verb tenses or other grammatical aspects for fluency, but they can reach stages of vocabulary and comprehension.
It is important to keep in mind that Autism is a spectrum disorder and each child is different. No two Autistic children are the same. It is incredibly important to assess each one and see what they are capable of.
This is also a great sight when working with students with disabilities.