Deaf/hard-of-hearing postsecondary students may have some misconceptions surrounding scientific concepts that might be partially ascribed to a lack of access to culturally-responsive forms of pedagogy. The Deaf and hard-of-hearing community is diverse in communication modes, including those who use American Sign Language as their primary language, and therefore, some students from this population may display characteristics similar to English Language Learners. Through classroom discourse analyses and interviews, we found a general lack of persuasion characteristics used by most students in an environmental science unit, and that the lack of higher-level scientific argumentation skills seemed to be related to students not having prior exposure to persuasive strategies. With the goal of improving Deaf and hard-of-hearing students' equitable access to quality science education, strategies should be considered in teaching approaches, and results suggest the need to include scientific argumentation tasks within sociocultural learning contexts. Ultimately, the goal is to work toward educating and engaging Deaf and hard-of-hearing students in science inquiry and improving the environmental scientific literacy of this underrepresented group.