Teacher students need a solid foundation in their subject matter, a clear understanding of teaching and learning, and the ability to integrate technology into their teaching. The TPACK framework assesses this comprehensive knowledge. This study explored how physics teacher students utilize educational technology for visualizing physical phenomena during lesson planning. The research involved ten first-semester physics teacher students and included two lectures, an online support session, and a one-hour workshop, with data collection focused on the workshop. The lectures introduced digital tools, emphasizing GeoGebra. Prior to the workshop, students evaluated GeoGebra simulations for teaching motion on an inclined plane. During the workshop, students were video filmed as they worked in pairs to discuss and modify simulations. The analysis was based on the TPACK framework, focusing on technology integration domains. The study found that most pairs collaborated effectively, demonstrating advanced TCK and a nuanced understanding of TPK. They evaluated the usability and motivational aspects of the simulations, highlighting their ability to leverage technology for engagement and understanding. The findings highlight the developmental process of integrating technology, pedagogy, and content, as outlined in the TPACK framework. By the end of the workshop, students exhibited some TPACK skills when using GeoGebra features to scaffold learning while maintaining scientific accuracy and pedagogical clarity. However, the results indicate room for further development of the participants’ TPACK. The TPACK framework, complemented by models for operationalizing physics teachers’ TPACK skills, provided a valuable structure to evaluate the students’ competencies in using GeoGebra for physics lessons.