The present study evaluates the effectiveness of Check & Connect (C&C) in a randomly assigned sample of students who were all receiving Communities in Schools (CIS) services. The research questions for the study include: Are there differences in attendance, academics, and behavior for CIS students who also receive C&C compared to students who only receive CIS services? Nine middle schools, four high schools, and one middle/high school located in a large urban region of the southwestern US comprised the setting for the study. This study used a randomized block design to examine the effectiveness of C&C on academic performance, behavior, and attendance with at-risk middle and high school students. Results provide evidence of the effects of C&C implemented in a real-world setting by school-based practitioners, situating effect sizes within the context of C&C being implemented under conditions that practitioners would normally experience. Tables and figures are appended.