In an effort to improve student learning, authentic research experiences have been incorporated into introductory laboratory courses as a means to teach students scientific inquiry and engage them in the scientific process. Here, we describe the development and implementation of a novel undergraduate research-based laboratory course for first-year students where students swap projects midsemester. Swapping research projects establishes reciprocal peer learning partnerships, thereby empowering students to simultaneously be both peer teachers and active learners in an introductory laboratory course. Our Crisscrossing Learning Experience (CCLE) course was designed to promote a high level of collaboration, sense of ownership, and science identity among first-year students through the learning by teaching paradigm and close mentoring.