Students who took the SAT earlier this month at a Northern Virginia high school might have to take the exam again after the paper tests were lost, a devastating prospect for those who spent weeks and hundreds of dollars preparing for the college entrance exam.

Tests for more than 260 students who took the SAT and SAT subject tests May 2 at Broad Run High School in Loudoun County went missing after they were sent via UPS to Educational Testing Service, which administers and scores the SAT. Loudoun schools spokesman Wayde Byard said the paper tests apparently never made it to ETS, and the company has scheduled a retest June 20.

“The shipment containing SAT and SAT Subject Test answer sheets from the Broad Run High School test center for the May administration has not yet been received,” ETS spokesman Jason Baran wrote in an e-mail Wednesday. “We share the frustration of affected students and their families. Every effort is being made to locate the shipment.”

Baran said the retest will be free for the students whose exams were lost. But that is little consolation for many of them, who scheduled the important exams so they would not interfere with finals and spent weeks preparing for them, sometimes in expensive prep courses scheduled specifically for the May test.

Vinay Bhawnani, who runs Loudoun Test Prep, said that approximately 20 of his students took the May exam. They each paid nearly $1,200 for an eight-week course that was designed to end just before they took the test.

Bhawnani said he fine-tunes his course so that students feel fully prepared — but not exhausted — when they take the SAT. He worries that many students will not perform as well on a retest as they did on the exam, noting that many will be taking finals the week before the retest.

“No one’s going to be up to par,” he said. “No matter what they do at this point, it’s not going to go as well as it could have.”

Bhawnani heard from students distraught over the lost scores and concerned that they would not be able to match their performance. He is offering a $300 boot camp, which includes two three-hour classes, the weekend before the retest to give students a refresher.

Michelle Disch, whose son Kyle took the Loudoun Test Prep course, said she is worried about her son’s performance on the retest because more than a month and a half will have passed since his last prep class. And she also is angry that the College Board never notified parents that scores were lost, informing them only of a retest date.

“The issue is really that we spent all this money on test prep,” Disch said. She plans to sign Kyle up for the refresher.

On Twitter, many students vented their frustration about the lost exams.

“Today has not been a good day,” one girl said. “Found out my SAT scores got . . . lost.”