This work is part of an ongoing work for sign language tutoring with imitation based turn-taking and interaction games (iSign) with humanoid robots and children with communication impairments. The paper focuses on the extension of the game, mainly for children with autism. Autism Spectrum Disorder (ASD) involves communication impairments, limited social interaction, and limited imagination. Many such children show interest in robots and find them engaging. Robots can facilitate social interaction between the child and teacher. In this work, a Nao H25 Humanoid robot assisted the human teacher to teach some signs and basic upper torso actions which were observed and imitated by the participants. Kinect camera based system was used to recognize the signs and other actions, and the robot gave visual and audial feedback to the participants based on the performance.