Our son has kept the preschool label of "Developmental Delay" even though he will be in a kinder/first grade autism classroom next year. I'm fine with the Developmental Delay category becasue it is a very broad term that involves different areas of development. They use this term mmore with younger students when it is not yet clear what their primary disability is. How old is your child? I would avoid "Intellectually Challenged" for a young student because it is difficult to assess the IQ of young kids, especially so if they are on the spectrum.