The purpose of this study was to explore how participation in iterative cycles of a modified model of lesson study could potentially provide preservice teachers opportunities to develop the ability to notice students' science thinking. Using a case study approach, we examined how six preservice teachers illustrated aspects of "professional noticing" while engaged in a modified model of lesson study during an early field experience practicum. We analyzed video and artifacts from five lesson study cycles, mapped how the preservice teachers professionally noticed throughout each cycle, and examined interactions between the three components of noticing. Participants' abilities to attend to student thinking ranged from general descriptions of how students were exploring and discussing the content, to detailing the specific actions and words of individual students (attending), and to identifying patterns of student thinking across the class and across the five lessons (interpreting). The preservice teachers were able to respond to students' thinking at various levels, thus demonstrating the ability to engage in the three components of noticing and sometimes connected their observations (attending) to their interpretations and their responses to how students were thinking. We believe participants' abilities to notice can be attributed to the iterative approach to our model of teaching, reflecting, and revising through the lens of assessing and revising lessons based on students' learning needs in an authentic context. Finally, we conclude with recommendations for supporting preservice teachers as they further develop their abilities to professionally notice. [Note: The second page is numbered as page 1, and there are two pages marked as page 17.]