The 9th grade shock and the high school dropout crisis.

Retrospective questions on educational attainment in national surveys and censuses tend to over-estimate high school graduation rates by 15-20% points relative to administrative records. Administrative data on educational enrollment are, however, only available at the aggregate level (state, school district, and school levels) and the recording of inter-school transfers are generally incomplete. With access to linked individual-level administrative records from a very large "West Coast metropolitan school district" we track patterns of high school attrition and on-time high school graduation of individual students. Even with adjustments for the omission of out-of-district transfers (estimates of omission are presented), the results of this study show that failure in high school, as indexed by retention and attrition, are almost as common as on-time high school graduation. In addition to the usual risk factors of disadvantaged background, we find that the "9th grade shock"-an unpredicted decline in academic performance upon entering high school-is a key mechanism behind the continuing crisis of high school attrition.