Researchers have shown rural elementary and middle-grade science teachers' inability to integrate STEM career-related lessons into their curricula despite engagement in professional development linked to the teachers' intent-driven beliefs. Researchers, however, have not investigated the influence of intentions on teachers' abilities to integrate STEM career-related lessons into science instruction. The purpose of this transcendental phenomenological study was to understand how intentions impacted rural elementary and middle-grade teachers' ability to integrate STEM career-related lessons during science instruction. Guided by Ajzen's (1988) theory of planned behavior, this study was designed to examine teachers' intentions to integrate STEM career-related lessons during science instruction and the underlying causes of such intentions. In this transcendental phenomenological study, reflective journal entries and interview data were collected through purposeful sampling of 10 rural elementary and middle-grade science teachers. Data were analyzed using a modification of the Van Kaam method of analysis. Findings showed that teachers intended to regularly integrate STEM career-related lessons, but needed more support from their administrators, colleagues, and community partners in fulfilling their intents to integrate STEM career-related lessons. Additional studies are needed for an increased understanding of how teachers in rural areas intend to integrate STEM career-related lessons amid challenges rural teachers face. This study may be of benefit to administrators and teachers who want to unite efforts in constructing a positive climate of integrating STEM career-related lessons during science instruction.