This paper presents interactive games for sign language tutoring assisted by humanoid robots. The games are specially designed for children with communication impairments. In this study, different robot platforms such as a Nao H25 and a Robovie R3 humanoid robots are used to express a set of chosen signs in Turkish Sign Language using hand and arm movements. Two games involving physically and virtually embodied robots are designed. In the game involving physically embodied robot, the robot is able to communicate with the participant by recognizing colored flashcards through a camera based system and generating a selected subset of signs including motivational facial gestures, in return. A mobile version of the game is also implemented to be used as part of children's education and therapy for the purpose of teaching signs. The humanoid robot acts as a social peer and assistant in the games to motivate the child, teach a selected set of signs, evaluate the child's effort, and give appropriate feedback to improve the learning and recognition rate of children. Current paper presents results from the preliminary study with different test groups, where children played with the physical robot platform, R3, and a mobile game incorporating the videos of the robot performing the signs, thus the effect of assistive robot's embodiment is analyzed within these games. The results indicate that the physical embodiment plays a significant role on improving the children's performance, engagement and motivation.