Although there is a general sense among educational researchers that t
he practice of ability grouping is widespread, national descriptive st
atistics on the subject are scarce. This note presents data from the N
ational Education Longitudinal Study of 1988 that suggest a sizeable m
ajority of 8th and 10th grade students are tracked. Also, it is found
that informal tracking patterns in the 8th grade and 10th grade seem t
o be broadly similar. Lastly, we note that students from low socioecon
omic backgrounds, blacks, and Hispanics are more likely to be enrolled
in lower track classes and less likely to be in upper track classes.