The sample included 6,609 students out of 7,707 (93%) enrolled in the 12 participating schools. Participants completed an average of 4.14 (SD = 2.06) assessments during up to 2 full years. Students were between 10 and 16 years of age at the time of their first assessment (M = 12.45, SD = 1.07). Participating students included 3,282 females and 3,243 males (84 students, 1.3% of the sample, did not report their sex). Forty percent of the sample (n = 2,641) identified themselves as non-White; of these, about two thirds were Latino, and the rest were primarily Native American.
