The study from the Fordham University Center on Law and Information Policy, released Wednesday, casts light on data systems created at the urging of the federal government to track student progress. One finding: States often fail to spell out protocols for purging records after students graduate.

"Ten, 15 years later, these kids are adults, and information from their elementary, middle and high school years will easily be exposed by hackers and others who put it to misuse," said Fordham law professor Joel R. Reidenberg, who oversaw the study. States, he said, "are trampling the privacy interests of those students."