In this action research, the interactions of seventh grade pre-algebra students in a mathematics classroom shared their explanation and justification processes through group work. Prior to the start of the study students were given a written pre-test to determine current conceptual thinking in mathematics. Over the next nine weeks, the teacher engaged the students in problem solving activities that included reasoning skills, communication and making connections through discussion with their peers. Following nine weeks of written and verbal discourse, students were provided a post-test to determine changes in their conceptual thinking. Overall students' grades, journal writings and test scores showed positive gains with the greatest changes occurring in written explanations of their conceptual thinking in mathematics.