Providing for students with learning challenges willl help all students comprehend. Many students with learning "disablities" are of average or above average intellegence. Finding new ways to reach one student will help you reach others. Not every student with a learning disability will know they have one. exploring new ways to facilitate comprehension will help the class as a whole!
Instructing learners with disabilities should not be seen as a burden, they are usually above average inteligent students.
What they might need is some special attention like:
More time
Talk to them about what is useful for their learning
Maybe they need a more quieter place to take the exams
