This study compared the academic performance and classroom behavior of Hmong-refugee first and second graders to those of classmates from other ethnic backgrounds. Two cohorts of children and families from six inner-city Saint Paul (Minnesota) elementary schools participated in this ongoing longitudinal study, for a total of 528 children entering kindergarten in 1992-1994. Half attended Head Start, with the remainder drawn from the same classrooms. Nearly half the children in each cohort were Hmong; others were Caucasian, African-American, Hispanic, or American Indian. Findings indicated that compared to other ethnic groups, Hmong children are more likely to live with both biological parents, have more siblings, and move less often. Hmong parents are more likely to be older and married and less likely to have a high school diploma. There was no significant ethnic group difference in reading achievement as assessed on the Woodcock Johnson Tests of Achievement-Revised (WJTA-R). Hmong children entered kindergarten with lower mathematics achievement scores as assessed on the WJTA-R, but these differences disappeared by spring of first grade. Teachers rated Hmong children as more cooperative, more self-controlled, and with fewer problem classroom behaviors. There was no difference in teacher ratings on assertiveness. Hmong children had higher school attendance rates than other ethnic groups. Stepwise regression analyses indicated that participation in the Transition Project and Head Start, smaller family size, and older parents predicted higher reading achievement. Higher school attendance and parent involvement predicted higher mathematics achievement. (Contains 11 references.) (KDFB)