Background: This study addresses how the modality of classroom drama and playwriting accentuated future teachers' pedagogical content knowledge (PCK) and their knowledge about developmental psychology for teachers. The study was framed in a bifocal model of PCK and a signature pedagogy, with the intersection of learning and acting in a play as an important component of the framework, which includes the knowledge of what the Vygotskian concept of a 'zone of proximal development (ZPD)' comprises. The study includes discussions about drama as an educative medium, specifically 'drama for learning in the classroom'. Aim: The research aimed to explore how the pedagogical power of classroom drama can diversify primary student teachers' repertoire of pedagogical tools. Setting: The study was conducted at an urban university in Gauteng. A total of n = 90 participants were purposefully selected to participate in the study. Methods: The methodology followed in this research was qualitative, and it employed a case study design in which the researcher investigated her practice as a practitioner-researcher. She investigated the students' classroom drama artefacts and conducted focus group interviews with participating students about their experiences during the playwriting course. Results: The findings revealed that students' engagement in the playwriting activity highlighted that they had moved from basic beginner authors to completing pedagogic plays that are usable in primary school classrooms. With that, they had reached 'higher mental functions' in their 'ZPD'. Conclusion: Using classroom drama as a pedagogy was beneficial for teaching vocabulary in Sesotho and isiZulu. Contribution: The study has also contributed to the field through the playwriting model with suggestions for several applications of classroom playwriting and performance.