This study investigates the effect of group collaborative argumentation on the quality of decision-making on waste incineration of socioscientific issues (SSI). To achieve this, fifty-nine high school students engaged with a lecture-style class that did not use any argumentation activities. They then completed an individual survey aimed at examining individual decision-making, as the pre-test. The participants then received a two-week pedagogical intervention of collaborative argumentation, after which they completed the same survey again, as the post-test. The results showed that, after the argumentation intervention, students made more statements that considered ethical issues and policies. In addition, students defended their positions with more in-depth analysis supported by sufficient and scientific evidence. These findings reveal that argumentation facilitates students' growth in interdisciplinary thinking and improves the quality of their decision-making on the SSI. Implication was group argumentation will be of great value to the more widespread implementation of the SSI curriculum.