The objective of this short-term longitudinal study was to examine individual versus classroom peer effects of grit on later individual literacy achievement in elementary school. The dual language learner, largely Latina/o sample included students from the 3rd through the 5th grades. Participants completed a literacy achievement performance task at 3 time points over 4 months, in addition to student-reported grit at the first time point. Classroom peer grit, not individual grit, was a strong, significant predictor of an individual's later literacy achievement, adjusting for previous literacy achievement, age, gender, home language, and classroom clusters.