This study was an ethnography of high school students working as apprentices in university solid state physics labs, as part of a summer science program. It was designed to explore the learning potential for high school students in such an environment. It examined the social interactions between scientists and students and how these constrain/support learning. Video-taped key laboratory instructional events and student public presentations of what they were learning in their labs were submitted to an interactional sociolinguistic analysis. Findings focused on important discourse links between presentations and lab activities. Students selected a subset of topics from a range of topics covered in lab instruction. Contextualization cues employed by student and scientist to make sense of Lab talk were modeled in the Presentation. Conceptual understanding in Lab was sometimes represented in Presentation appropriately, sometimes vaguely or inconsistently. The speaker's vagueness was usually not apparent to the audience of a Presentation. A learning model for high school students in research labs is proposed based on the findings. The characterization of students learning in university research labs lays a foundation for a match between doing science in such research labs and doing science in school labs. (Author)