The purpose of the study was to observe the indicators of science teachers' technological pedagogical content knowledge (TPACK) using a video-based research method. The study was conducted with four in-service science teachers who taught at a school that offered tablet-based education in primary and secondary levels. Data sources included video-recorded classroom teaching sessions and pre- and post-video teacher interviews. In addition to the in-depth contextual information provided, the findings from the qualitative analysis of teacher cases revealed indicators of teachers' TPACK in their lesson design and actual teaching processes. Design indicators included technology selection, curriculum planning, lesson preparation, and assessment. Actual teaching indicators included lesson entry behaviors, teaching methods and strategies, technology-enhanced classroom management, troubleshooting, and assessment.