This study investigates computer programming ('coding') activities of Primary School Children; we ask if there is evidence of gender differences in their coding activities. The research took place in an English urban school with around 180 children on role, mostly from a middle-class social background. The study involved a class of 17 boys and 15 girls aged 10-11 years. Teaching was delivered by the class teacher using our 'WeeBee engine', where children code animated stories using the professional text-based language Java. We first review relevant literature about gender differences to develop criteria for our analysis. We assess the children's code, their process of coding and the quality of their final animated stories. Our findings strongly suggest there are no gender differences in coding ability and in the quality of stories created. We suggest that practitioners should not assume that gender differences exist in this context, and they should not adapt their teaching to gender. The WeeBee engine is established as being gender neutral and we recommend its use by practitioners.