This Statistics in Brief provides descriptive statistics on algebra enrollment for the cohort of students in the first-grade class of 1999-2000 who had progressed to eighth grade in the 2006-07 school year (representing about 80 percent of the eighth-grade class of 2006-07). The Brief examines mathematics performance at the end of eighth grade by algebra enrollment and other characteristics, including prior mathematics ability and schools' level of eighth-grade algebra enrollment. Data are drawn from the Early Childhood Longitudinal Study, Kindergarten Class of 1998-99 (ECLS-K), which included a direct mathematics assessment at the end of the fifth and eighth grades.