Social robots have led to a growing body of research, and continued to demonstrate potential benefits for education, rehabilitation, and special education. The main research questions of this study were: what are preschool children's questions to the social robot? What are preschool children's reactions to activities led by the social robot? Zenbo, developed by a Taiwanese company, was chosen as the experimental social robot. Sixty-nine children aged 5-6 were recruited from preschools for this study. The researcher used an observational method to collect data regarding the children's questions and responses to Zenbo. Data analysis included two parts: (1) questions raised by children to Zenbo; (2) children's attention rate among the three activities-questioning, story-telling and rhyme movement. The result showed that children's questions to Zenbo can be categorized as follows: questions similar to daily conversations among human beings, questions related to Zenbo's functions and abilities, and questions to test Zenbo's purported omniscience. This study demonstrated that the overall attention rate of children was high (above 95%) for the different activities. Based on the findings, recommendations were made by the researcher.