Tracing changes in teachers' professional learning network on Twitter: Comparison of teachers' social network structure and content of interaction before and during the COVID-19 pandemic.

Background: The COVID-19 pandemic has affected teaching and professional learning activities. Teachers may have to rely on online spaces, such as Twitter, to interact with their professional learning networks and get enough support.

Objectives: This study aims to investigate the structure and the content of teachers' network interactions on Twitter both before and during the COVID19 pandemic.

Methods: Data were analysed for 103 teachers using multiple methods, including social network analysis (SNA) and content and thematic analysis.

Results And Conclusions: Content analysis revealed that teachers' cognitive and affective posts increased significantly during COVID-19. Thematic analysis showed that, during COVID-19, teachers' post sfocused on issues around digital transformation. SNA showed that the sizes of teachers' networks and in/out-ties grew during COVID-19. Although the study finds that teachers interacted with individuals both within and outside their discipline and their country, most teachers' interactions were with teachers from similar disciplines and same country. Teachers used Twitter to share information and support each other.

Implications: This study provides recommendations for stimulating professional interactions among teachers. This work shows the potential of SNA and content analysis to analyse teachers' professional learning networks.