The purpose of this study is to test the feasibility and initial efficacy of an after-school social intervention delivered by paraprofessionals in school settings for higher-functioning children with autism spectrum disorder (hfASD; without intellectual disability). Feasibility will be assessed via implementation fidelity (accuracy), parent and child satisfaction ratings, and attendance and attrition rates. Outcomes will test the intervention effect on social-cognition, social skills, ASD symptoms, and social competence. For feasibility, it is hypothesized that: (1) paraprofessionals will demonstrate fidelity \>90% throughout the social intervention; (2) satisfaction ratings will be high (parents will report an average satisfaction item M\>6.0 and children will report an average satisfaction item M\>5.0 of a maximum 7=completely satisfied); (3) the attendance rate will be \>90% (on average) across the program; and (4) the attrition rate will be \<5%. For child outcomes, it is hypothesized that children in the social intervention group will demonstrate significantly greater improvements compared to the no-treatment control (waitlist) group in social-cognitive knowledge, parent ratings of social skills, parent ratings of ASD symptom severity, and ratings of social performance (measured via direct behavioral observations by masked raters). It is also hypothesized that children initially randomized to the social intervention group will maintain the intervention effects three months after the social intervention.

A pilot randomized controlled trial (RCT; pretest-posttest control group design) will be conducted. Children will be recruited using announcements disseminated by district administrators and parents and children will be required to provide written parental consent and written child assent initially for participation in the screening (to determine eligibility) and subsequently for participation in the social intervention study (for those meeting eligibility criteria). Paraprofessionals will complete a 20-hour training and demonstrate \>90% fidelity implementing the intervention. Children will be randomly assigned by the study statistician to the social intervention group or no-treatment control (waitlist) group. The manualized social intervention is then delivered to those randomized to the social intervention group on-site at the students' schools as part of the schools' existing after-school programming provided by paraprofessionals. The social intervention is delivered four days per week (90 minutes per session) over eight weeks in group format. Sessions are structured and include social skills groups, social recreational games, and a reinforcement system. Each group will be facilitated by two paraprofessionals, and include 12-15 children including two with hfASD (the remaining will be typically-developing peers). A comprehensive set of fidelity monitoring procedures are used to track implementation accuracy in the social intervention group, as well as document any therapeutic services received by the control group children. Satisfaction ratings (parent and child) are collected after completion of the social intervention. Child outcome measures are completed for both the social intervention group and no-treatment control (waitlist) group immediately prior to (pretest) and following (posttest) the eight-week intervention, and children initially assigned to the social intervention will also complete the assessments three months later (follow-up). Children assigned to the no-treatment control (waitlist) group will receive the social intervention after the intervention group completes the social intervention.