Examination of Differences in Height, Weight, and Body Mass Index (BMI) of Students from Two Disparate School Districts in Central New Jersey

School-collected data on height, weight, and body mass index (BMI) offers tremendous potential for examining differences in the growth and development of students in varying environments. This study examines data on height, weight, and BMI of 1858 students, in kindergarten through eighth grade, from two school districts in central New Jersey that are geographically close, but that are distinct in composition regarding their self-identified primary ethnicity and socioeconomic environments. In one district, 78.6% of the students identify as Hispanic or Latino, and in the second district, 88.9% of the students identify as White. Mann–Whitney U tests and a Kruskal–Wallis test were run on height, weight, and BMI, comparing median values of the students from the two districts by grade and ethnicity, respectively. These results, combined with results from a Dunn post hoc pairwise test, indicate that the significant differences could be attributed to socioeconomic status or self-identified primary ethnicity. Upon further testing, however, comparing students of different self-identified primary ethnicities within districts and comparing students within the same self-identified primary ethnicity across districts reveals a stronger association with socioeconomic status. Overall, the students in the less affluent population were shorter and heavier than the students in the more affluent population.