"Students with disabilities are the ones who are affected most by the language skills of the other children in their class," Justice said.
"We found that children with disabilities get a big boost in their language scores over the course of a year when they can interact with other children who have good language skills."
In fact, after one year of preschool, children with disabilities had language skills comparable to children without disabilities when surrounded by highly skilled peers in their classroom.
"The biggest problem comes when we have a classroom of children with disabilities with no highly skilled peers among them," Justice said. "In that case, they have limited opportunity to improve their use of language."
Justice added that highly-skilled children's language abilities were not negatively affected by having the special needs children in their classrooms.
Image: Preschool letters and numbers, via Shutterstock