Why do socioeconomic disparities in achievement emerge so early in life? Previous answers to this question have generally focused on the perceived deficits of parents from disadvantaged backgrounds (e.g., insufficient childrearing knowledge). Here, we instead focus on the structure of early childhood education and argue that early schooling contexts provide unequal opportunities for engagement to children of higher versus lower socioeconomic status (SES). As engagement is a longitudinal predictor of achievement, early SES disparities in engagement could serve to maintain or even exacerbate SES disparities in achievement. In Study 1 (1,236 observations; N = 98 children), we investigated preschool students' behavioral engagement during whole-class discussions-a core aspect of early childhood education. Low-SES children showed significantly lower engagement than their peers. Consistent with the claim of unequal opportunities for engagement, these differences were not accounted for by SES differences in language proficiency. As students' engagement in school is influenced by their peers' attitudes toward them, we also examined peer perceptions (Study 2, N = 94, and a meta-analysis, k = 2 studies). We found that preschoolers who show more engagement relative to others during whole-class discussions are perceived as possessing more positive qualities (e.g., intelligence). Given that higher-SES students are afforded more opportunities for engagement (see Study 1), they may be the ones benefiting from these positive peer perceptions as well, which might further boost their engagement. Our results suggest that aspects of early childhood education should be redesigned to foster engagement among all students, regardless of their SES.