Education Impact and Implications Statement We conducted focus groups and interviews with 68 racially diverse students in urban high school science classrooms to better understand their experiences with trying to assert themselves in the classroom to influence the motivational quality of the instruction they receive (agentic engagement). Results revealed that students can identify a variety of strategies for agentic engagement but rarely use them or see peers use them. Nonetheless, they experienced agentic engagement strategies as effective, especially under the right conditions (e.g., teachers are encouraging, students assert agency with respect), for creating a motivating learning environment for themselves, their teachers, and peers in the classroom. Results highlight the potential of agentic engagement for transforming the motivational climate of the classroom and the need for teachers to be open to and supportive of it in their classrooms. Agentic engagement refers to students' proactive and constructive contribution into the flow of classroom instruction and activities. Given its potential as a student-initiated pathway to promoting motivation and learning, the goal of this study was to describe agentic engagement from the perspectives of racially diverse students in urban high school science classrooms. A secondary goal was to consider the relation between belonging to an underrepresented group in science (i.e., female, Black, and/or Latino) and thoughts and behaviors pertaining to agentic engagement. We conducted focus groups and interviews with 68 students using phenomenological methods to examine what, how, why, when, and who questions regarding the use of agentic engagement in science classes. Results focused on the following themes. (a) Students identified a variety of strategies for enacting agentic engagement (e.g., suggestions), though their use was described as rare. (b) Students emphasized the importance of style or approach for enacting agentic engagement in constructive and effective ways, with Black and Latino students noting the importance of avoiding disrespect and approaching teachers privately and girls mentioning using a group approach. (c) Students identified three rationales for agentically engaging, including to elicit teacher support, support personal experiences of motivation and learning, and create a more desirable learning environment for the classroom community. (d) Students discussed a variety of factors that made agentic engagement more or less likely, including teacher factors (e.g., encouragement, discouragement) and student factors (e.g., personality). Boys mentioned teacher encouragement more frequently than girls. Implications for theory, research, and practice are discussed.