A "math congress" is a pedagogical approach in which students present their solutions from their mathematical work completed individually, in pairs, or in small groups, and share and defend their mathematical thinking. Mathematical artifacts presented during math congress remain on display as community records of practice. Math congress has four key functions: To highlight and document key mathematical concepts, to emphasize connections between different mathematical strategies, to facilitate conceptual development, and to scaffold learning by drawing attention to the efficiency of particular strategies. The goal of the research was to analyze the role of the math congress in eighth-grade students' development of mathematical thinking. Results suggest that while math congress was helpful for some students, other students articulated continued uncertainty about their mathematical thinking. Pedagogical recommendations as well as future research direction are discussed. (Contains 3 footnotes and 4 tables.)