LOUISVILLE, Ky. (WDRB) -- About 230 students at Atherton High School will have to retake a portion of the same college-credit exam that was postponed at two other local schools last week.

Atherton principal Tom Aberli said in a letter sent home to parents on Tuesday that due to an "issue outside of our school that had the potential to impact a portion of the AP Human Geography exam."

He said the testing administrator and school administrators have "collaboratively decided that our students will need to retake the free-response portion of the exam to assure testing security."

That portion of the exam has been rescheduled for Thursday, Aberli said, adding that 234 students took the free-response portion of the exam on Friday.

"All (AP Human Geography) students will need to retake the free-response portion or risk not having a valid score for the exam," he said.

Last Friday, 349 freshmen at duPont Manual High School were stopped from taking the free-response portion of the AP Human Geography exam in order to "protect the interests of our students" after the test administrator, Educational Testing Service, learned of a potential issue, according to Jerry Mayes, the principal of Manual.

The Manual students impacted by that postponement will take a different version of the test on Thursday, according to another letter sent home by the school on Tuesday.

In addition, the same test was postponed for AP Human Geography students at Assumption High School on Friday.

Assumption principal Martha Tedesco told WDRB on Tuesday her students will take the free response section of the exam on May 25.

"We received credible evidence of a testing breach regarding the integrity of the AP Human Geography exam at another area high school," she said. "We have been assured that there are no concerns regarding AP testing at Assumption High School. We cannot comment further at this time as this is an ongoing investigation."

School officials and officials with Educational Testing Services (ETS), which administers the College Board AP Exams, would not specify to WDRB what the concern is over the test and why it was postponed at Manual and Assumption or why students at Atherton have to retake the exam, other than to say it is "exam integrity" issue.

Aberli said he was first informed about the issue by ETS on Monday. He said the issue pertains to a "Post-It note that had items on it that were similar to those that would be on the assessment."

When asked Tuesday if any other schools were involved with the testing issue, a spokeswoman for JCPS said she "wasn't aware of it."

Jennifer Brislin, a JCPS spokeswoman, told WDRB that "ETS is still examining the issue (at Manual) and can’t give more details at this time."

"The test will be administered the same way, but students will take a different version of that portion of the AP Human Geography Exam than the version they would’ve taken on May 13," Brislin said. "This version was developed to the same specifications as that in the May 13 exam, with the same format, number, and types of questions."

Tom Ewing, a spokesman for ETS, told WDRB on Friday that only Manual and Assumption were impacted by the issue.

Ewing has not returned two emails from WDRB on Tuesday and today seeking comment.

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Reporter Antoinette Konz can be reached at 502-585-0838 or @tkonz on Twitter.

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