Little is known about how children and adolescents evaluate unequal teacher allocations of leadership duties based on ethnicity-race and gender in the classroom. U.S. boys and girls, White (40.7%), Multiracial (18.5%), Black/African American (16.0%), Latine (14.2%), Asian (5.5%), Pacific Islander (0.4%), and other (4.7%) ethnic-racial backgrounds, 8-14 years, N = 275, evaluated teacher allocations of high-status leadership positions favoring specific ethnic-racial or gender groups during 2018-2021. Adolescents, more than children, negatively evaluated unequal teacher allocations of leadership duties that resulted in group-based inequalities, expected peers who shared the identity of a group disadvantaged by the teacher's allocation to view it more negatively than others, and rectified inequalities. Understanding perceptions of teacher-based bias provides an opportunity for interventions designed to create fair and just classrooms that motivate all students to achieve.