BACKGROUND AND OBJECTIVES Adolescence is a critical period for cognitive, social, and emotional development. Existing data on dose-dependent associations between cannabis use and adverse psychosocial development indicators in adolescence are limited, particularly for low-frequency users. We describe relationships between cannabis use frequency and psychosocial indicators. METHODS This cross-sectional study used a US nationally representative sample of 8th, 10th, and 12th grade students from the 2018-2022 Monitoring the Future surveys. Participants were categorized for nonuse and noncurrent, monthly, weekly, and near-daily cannabis use. We describe demographically adjusted odds of cannabis use frequency and cognitive, social, and emotional indicators. RESULTS Among 162 532 respondents (mean age, 16.0 years [SD, 1.7]; 45.8% male; racially and ethnically diverse), 42 601 (26.2%) were cannabis users: 7515 (4.6%) were near-daily, 5853 (3.6%) were weekly, 7802 (4.8%) were monthly, and 21 431 (13.2%) were noncurrent users. Compared with nonusers, noncurrent and monthly users had greater odds of poor academic performance (adjusted odds ratio [aOR], 1.30–2.20), poor impulsivity and self-regulation (aOR, 1.26–2.19), and adverse emotional states (aOR, 1.1–1.42). Adjusted odds of all adverse psychosocial categories, excluding low social engagement, showed a consistent dose-response trend. Effect sizes were small for poor academic performance (d = 0.39–0.44), small to medium for poor impulsivity and self-regulation (d = 0.43–0.55), small for adverse emotional state (d = 0.33–0.40), and none to small (d = 0.03–0.18) for low social engagement. Younger users (aged <16 years) showed greater susceptibility for academic and emotional indicators. CONCLUSION In this nationally representative sample, dose-dependent associations of frequency of cannabis use with adverse academic and emotional functioning were observed, even among monthly users, underscoring the importance of routinely inquiring about cannabis use in adolescents.