The past two decades have witnessed substantial interest in sluggish cognitive tempo (SCT), a set of symptoms (e.g., excessive daydreaming, mental confusion, slowed behavior) distinct from attention-deficit/hyperactivity disorder (ADHD) and other psychopathology symptoms. Despite evidence linking SCT to a range of functional outcomes, findings for academic functioning are unclear. The current review summarizes the literature on SCT and academic functioning and offers an agenda for future research. A systematic review was conducted to identify studies assessing SCT and academic outcomes, including academic impairments and performance, in childhood, adolescence, and young adulthood. Sixty studies were retained (53 cross-sectional, 7 longitudinal) from 44 separate samples, with the majority (n = 32, 53%) assessing global ratings of academic impairment and fewer measuring specific academic domains or standardized achievement test scores. Findings were generally consistent in showing SCT to be correlated with global ratings of academic impairment, lower grades, and inconsistently associated with poorer math and reading scores. Findings were more mixed when controlling for ADHD symptoms, intelligence, and/or demographic factors. Overall, SCT is associated with poorer academic functioning, although inconsistencies and key limitations are common across studies. Ten directions for future research are offered to advance understanding of how SCT may be associated with or impact academic functioning.