The science education field has a long tradition and interest in mapping its community and research using mostly bibliometric methods. At the same time, there has been growing interest in studying scientific collaboration and its network pattern. Many of these studies on the dynamics of social networks focus on well-established communities, while studies examining the union of communities are rare. As such, the primary purpose of this study is to fill this literature gap by investigating the science education research field that is grounded in cultural-historical activity theory (CHAT) through a coauthorship network. Our data include 86 Brazilian science education scholars with their coauthors. In total, we consider 554 unique papers written in English, Portuguese, and Spanish over the past 30 years. We found an increasing trend in coauthored papers, resulting in a higher collaborative coefficient over time. It turns out that the topological metrics support that the considered researchers form a cohesive core-periphery community with relatively few connected components, a high tendency for clustering, relatively low path length, and a heterogeneous distribution of node degree. We have verified that the available community presents structural and dynamic properties of mature research fields, and scholars are introducing their collaborators to one another, creating new social acquaintances resulting in coauthorship. Nevertheless, studies on science education ground in the CHAT framework do not rely on international collaboration. Finally, the conducted analysis indicates several fruitful avenues for future research.