This study investigates elementary pre-service mathematics teachers' noticing in a video-based activity within the context of a mathematics teaching methods course. To this end, we analyzed what and how pre-service mathematics teachers noticed in the Public Release Third International Mathematics and Science Study (TIMSS) videos. Data obtained from pre-service teachers' written analysis of classroom teaching videos were then analyzed. The results indicate that pre-service teachers primarily focused on "discourse" followed by "task" and "learning environment" aspects of the classroom teaching presented in the videos. While pre-service teachers' noticing was primarily descriptive and evaluative in a general sense, there was less interpretive level noticing. It was interesting that most comments belonging to the interpretive level appeared in the task category. Additionally, pre-service mathematics teachers generally noticed the elements of instruction related to teachers (i.e., the teacher's role, movement, and pedagogy) at descriptive and evaluative levels, but were less attentive to how specific classroom events, tasks, or content were connected with students' learning. Our findings suggest that exposing pre-service mathematics teachers to multiple contexts and diverse mathematical content during the analysis of video cases of classroom practices in collaborative environments supports noticing specific aspects within classroom practice.