The Better Math Teaching Network (BMTN) is looking to transform high school math instruction in New England and beyond. Through this network, researchers and practitioners are working together to make high school Algebra I classes more student centered. This report outlines findings from the first year of this developmental evaluation of the Better Math Teaching Network. The aim was to provide a descriptive and analytic portrait of the network's first year of operation. The authors drew on a range of data sources to examine this networked improvement community (NIC) in action, including: (1) Observations of whole- and small-group network meetings; (2) Interviews with participating teachers conducted at multiple time points throughout the year; (3) Teachers' responses to a survey designed to measure teachers' experiences with key features of the NIC concept; (4) Analysis of teachers' formal and informal connections to one another that are facilitated by the network; (5) Documentation teachers generate through their improvement cycles; and (6) Classroom observations and follow-up interviews with a small sample of teachers. The findings are presented in two ways. First, the authors present three in-depth case studies that describe how teachers with different motivations, experiences, and local contexts benefited from participation in the network. Then chart essays are presented, which describe key themes that emerged from the authors' analyses.