Children with developmental disabilities are trained using different teaching arrangements. One of these arrangements is called small-group teaching. It has been ascertained that a small-group teaching arrangement is more effective than a one-to-one teaching arrangement. In that sense, teaching academic skills to pre-school children in small-group arrangements is crucial in order to make them ready for their future educational environment. Considering this, the present study investigated the effectiveness of the constant time delay procedure in teaching pre-school academic skills to children with developmental disabilities in a small group teaching arrangement. It was also examined to what extent learning through observation can be achieved using the small-group teaching arrangement with a constant time delay. The study was conducted using four children with developmental disabilities between the ages of four and six. The multiple probe design across behaviors was applied individually to the four subjects in the study. The findings indicated that the use of constant time delay teaching in small-group arrangements was effective for children with developmental disabilities in teaching different pre-school academic skills using different stimuli. Furthermore, it was observed that the children acquired the skills more precisely through observational learning.