Updated

Seventeen New York City high-school students already at risk of dropping out will have to retake state exams required for graduation after the city lost their answer sheets, school officials said Friday.

The city isn't sure what happened to the 17 U.S. history exams, which were being shipped from one school to another as part of a pilot program of new grading procedures, schools spokeswoman Erin Hughes said.

About 107,000 exams from 162 schools were shipped among schools as part of a transition to new rules that prevent teachers from grading students from their schools.

The exams were supposed to be packed up in a box of more than 100 exams taken by night-school students at a Young Adult Borough Center located in the Franklin D. Roosevelt High School in Brooklyn.

The centers are an alternate way to graduate for students who are at least 17½ years old and have been in high school for four years.

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