The Research-in-Instruction Lab (RI-Lab) model is an analogue of the surgical theater in medical schools and is intended to make expert mathematics teaching visible to and able to be studied by teams of mathematicians, education researchers, experienced and new teachers, and pre-service teachers. The RI-Lab is designed to serve as an incubator for instructional practice and interdisciplinary research into practice. The investigators have developed elementary mathematics labs (EMLs) and replication of the strategy in other locations has seen varying success. This EAGER project is elaborating and specifying the design of RI-Labs to support structured experimental work on instruction in mathematics at the elementary and secondary levels. The researchers are creating and studying secondary mathematics labs (SMLs) as an outgrowth of the EML model, articulating more precisely the research, collaboration, and learning that the larger definition of RI-Labs engender, in an effort to specify the important features of the RI-Labs model, under the hypothesis that once specified, this model will have the potential to enable high-payoff research that could transform education research on a large scale. The study consists of characterizing features of the labs in relation to what the instructional intervention is, how it is studied, and who studies it. Four research questions are being addressed: 1) How and why do different groups of participants use the laboratory class? 2) What work is involved in making elements of teaching visible to and learnable/study-able by observers? 3) What are the affordances and challenges of public engagement with teaching across different groups of participants? 4) What learning opportunities are afforded by an RI-Lab design? New knowledge created by this project is being shared with the NSF Math and Science Partnership and DRK-12 communities and with the public. The ultimate impact of the project, if successful, will be to provide a well-articulated model that can be replicated to advance a new paradigm in education research.