The aim of this study was, first, to investigate any pattern between students' quantitative contribution to argumentation and their science understanding, and second, to analyze any relationship between students' qualitative contribution to argumentation and their scientific knowledge. Participants of the study were four tenth-grade students. The participants were videotaped during the argumentations embedded in the physics class. Two interviews were conducted with each participant in order to examine their scientific understanding deeply. Argumentations were analyzed as quantitative and qualitative by using Toulmin's Argument Pattern. Results from the study illustrate no significant relationship between students' engagement in argumentation and their science content knowledge. (Contains 4 tables and 1 figure.)