Child Computer Interaction (CCI) research stresses the importance of nurturing children's designer and maker identities; children should be growing up as future technology protagonists, who are driving technology development and critically reflecting on it. While the importance of designer and maker skills has been emphasized in the CCI literature, studies focusing on children's identity development are scarcer. This paper starts to fill this research gap. We develop a theoretical framework on children's technology protagonist identity based on multidisciplinary literature base. Based on pre- and post-interview dataset from a long-term critical design and making project with several school-classes, we identify divergent aspects of protagonist identity among children: they position themselves variably as technology users, designers, makers, critics and activists. Different designer and maker identity trajectories are also identified. The paper contributes to CCI research on identity and CCI discourse on technology protagonists and children's technology education.