Since contemporary learning theories, strategies and models offer the interdisciplinary approach, educators need new pedagogical alternative ways to attain it in practicum. For this reason, the current research aimed to illustrate how to intertwine mathematical modeling with an environmental issue that recruits waste management (e.g., reuse-recycle-reduce) to live an environmentally friendly lifestyle. Through a case study research, 6 seventh-grade students (3 females and 3 males; aged 13-14) voluntarily participated in the research. The researchers videotaped and analyzed all interactive learning processes to elicit the students' environmental dialogues. The results indicated that the interdisciplinary mathematical modeling afforded the students to acquire the targeted environmental concepts/issues and somewhat supported their arguments. Since the current research illustrates an alternative pedagogy to integrate science/environmental education into mathematics, it may be used to facilitate dissemination and applicability of the STEM education.