This study explored the effects of arguing to learn in a socioscientific context on the fundamental and derived components of reading, writing, and science understanding as integral parts of science literacy. We adopted mixed-methods in which the 1-group pretest-posttest design with supplemental interviews and questionnaires. The pretest evaluated the dependent variables (reading and writing scores), the treatment was arguing to learn about the global climate change issue, the posttest evaluated the dependent variables, and follow-up questionnaires and interviews informed the quantitative results. An intact grade six class (N = 28) at an urban elementary school located in central Taiwan was the participants. Analyses of the pretest-posttest gain scores and correlations between these outcomes revealed significant (p < 0.05) improvements in writing and associations among reading, writing, and arguing to learn. Interpretation of the qualitative data (interview and questionnaire responses) supported that argumentation as an instructional treatment focused on fundamental literacy could play a positive role in facilitating students' enhanced science understanding (derived literacy).