Inequities in STEM participation for people of color and women are documented extensively, often highlighting issues of representation and/or achievement. This study adds to the literature by looking at participation inequities in a high school calculus class. Equity is conceptualized as a fair distribution of opportunities for students to engage in rich mathematical experiences. Analysis of participants' dialog revealed talk about student participation focused primarily on gender patterns, even when pertaining to only one race-gender group of students (i.e., White males). Analysis of whole-class participation showed White dominance superseded male dominance; White males had the most robust opportunities to participate followed by White females, females of color, and males of color. Findings suggest participants' gender-focused discourse obscured racial inequities in classroom participation. [For the complete proceedings, see ED630210.]