In a really interesting review of adolescent studies, Robert Crosnoe and Monica Kirkpatrick Johnson point out that longitudinal studies are really only now becoming a resource to inform our understanding of adolescence. Citing one of these, they explain how important early learning has been shown to be to adolescent education. Crosnoe and Johnson write:
“By following Baltimore schoolchildren from first grade into early adulthood, Alexander and associates (2007) were able to capture the full educational career and, in the process, identify critical periods. Socioeconomic disparities in academic progress at the start of high school were traced back to corresponding disparities in place at the start of first grade and to summer learning differences by socioeconomic status during the elementary school years. These ninth grade differences were then linked to curricular track, high school completion, and college attendance. Their interpretation emphasized how foundational the skills are that are learned in the early years of schooling and the ways in which the in-school and out-of-school settings and experiences that stratify early learning can have lasting, even accumulating, consequences for the life course. Exclusive focus on the adolescent years, and particularly the high school years, misses these processes set in motion much earlier and likely obscures the best points of intervention (Heckman 2006).”
Ref: Robert Crosnoe and Monica Kirkpatrick Johnson (2011) Research on Adolescence in the Twenty-First Century. Annual Review of Sociology 37:439–60
Reference is to: Alexander K, Entwisle D, Olson L. 2007. Lasting consequences of the summer learning gap. Am. Sociol. Rev. 72:167–80 [ie American Sociological Review]
Heckman J. 2006. Skill formation and the economics of investing in disadvantaged children.