Direct Instruction Language for Learning in Autism Spectrum Disorder

Inclusion Criteria: * Meets one of the following age and Clinical Evaluation of Language Fundamentals -version 4 (CELF-4) or Clinical Evaluation of Language Fundamentals Preschool-2 (CELF-P) score combinations: * Males and females \> 4 years and \< 7 years 11 months of age in with a score \< 80 on the CELF-4 or the CELF-P, or * Males and females \> 5 years and \< 7 years 11 months of age with a score \> 40 on the CELF-4, or * Males and females \> 4 years and \< 6 years 5 months of age with a score \> 45 CELF-P * Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) diagnosis of autism spectrum disorder (ASD) established by clinical assessment, corroborated by the Social Communication Questionnaire and the Autism Diagnostic Observational Schedule * A score \< 80 on the Core Language score of the Clinical Evaluation of Language Fundamentals - 4 if \> 6 years 5 months * Stable educational plan with no planned changes in the intensity of treatment for 6 months * Stable community treatment program (e.g., speech therapy or occupational therapy) with no planned changes in the treatment for 6 months. (Otherwise eligible subjects with anticipated changes in their community treatment program in the near term will be invited to return when the transition has been accomplished). * English is spoken in the home and at least one parent is able to read, write and speak English * Psychotropic medication free or on stable psychotropic medication (no changes in p…