Student achievement is rooted in a teacher’s ability to identify and assess student understanding of material. This is particularly challenging in classroom settings, which are dynamic and full of distractions, especially in science classrooms where discussion and inquiry are paramount. In mathematics education, the concept of professional noticing of children’s thinking refers to a teacher attending to, interpreting, and responding to student content understanding throughout a class period (Jacobs, Lamb, & Philipp, 2010). This skill is equally important when teaching other content, such as science, and is a key component of responsive and reflective practice used by excellent educators as outlined by reform standards for science (National Research Council [NRC], 1996, 2012; NGSS Lead States, 2013). Before a teacher can adapt to student needs, they must first identify critical moments of student sense-making and interpret the student’s ideas. Only then can they respond effectively. This set of teaching skills can be learned, and then later improved upon with practice and reflection. Recent research suggests that preservice science teachers can learn the fundamentals of noticing skills during specialized courses (Barnhart & van Es, 2015) and are able to carry forward this learning into their teaching experiences as full-time teachers (Amador, Carter, Hudson, & Galindo, 2017). However, little is known about the role of different aspects of preservice teacher education program experiences in laying the foundation for life-long development of noticing skills. This study used a multiple case study design to explore the experiences of six preservice science teachers, as related to professional teacher noticing of student thinking about science, during the semester before their full-time student teaching experience. Based on a situated learning framework (Lave & Wenger, 1991), this study centered on the university- and field-based experiences associated with a middle and secondary teacher education program at a large, Mid-Atlantic, urban university. Participants were enrolled in a teacher residency program. Observations, semistructured interviews, and artifact analysis were used to identify opportunities for and experiences with learning professional teacher noticing of student thinking about science content throughout the first semester of this residency program. Analysis of data included the use of a combination of a priori codes about the degree of teacher noticing of student thinking about science (Barnhart & van Es, 2015) and emergent codes of contextual events relating to opportunities for preservice science teachers to notice student thinking during field experiences. Case studies were developed, and a cross-case analysis performed to identify themes and trends in the learning experiences and development of the participants around noticing practices. Broadly, I found that the most access residents have to noticing is in their field experiences, and that their opportunities to learn to notice may be primarily mediated by their mentors’ abilities to “unpack” their own practice, communicate effectively with the resident, and help residents hone in on the content goals of lessons. This study provides a unique examination of preservice science teacher learning opportunities at the interface of education coursework and field experiences. Assertions developed from this multiple case study analysis provide insight into which experiences have the most impact on the development of preservice teachers’ attention to student thinking. / Math & Science Education