Course-based undergraduate research experiences (CUREs)have been shown to result in increased science, technology, engineering, and mathematics (STEM) persistence, but such experiences are rarely available for first-year STEM students. This work outlines the development and integration of a CURE into a year-long honors general chemistry laboratory sequence involving the detection of microplastics in a local watershed with Nile Red. This CURE was implemented over three academic years in collaboration with a local environmental preservation organization. Samples were collected as part of a field sampling trip with students, and a pre/post-questionnaire was administered each semester. The questionnaire investigated how this CURE impacted students' self-concept as scientists and behaviors regarding plastic use. Additionally, interviews were conducted with CURE and non-CURE laboratory students. Outcomes of participation in the CURE versus the traditional (non-CURE) sequence are discussed, including pre/post questionnaire results, inductive coding of interviews, and microplastic counts in Cahaba River water samples. Results demonstrate that this CURE is beneficial for students' scientific self-concept and results in self-reporting of environmentally conscious behaviors around plastic use. This experience is appropriate for first-year STEM students but can be scaled to an upper-division laboratory or scaled down to a multiweek laboratory activity.