The University of Maryland is investigating 12 students for allegedly using their cell phones to dial up all the right answers during fall exams.

The students are accused of using the "text messaging" functions on their phones or pagers to receive silent messages from friends who had access to answer keys for the tests, campus officials said yesterday.

It is the latest wrinkle in the continuing struggle between technology and academic integrity. Though quick to jump on the Web and embrace the laptop, schools across the country have been confronted with the problem of students using those very tools to plagiarize essays from the Internet. At Maryland, as at many other colleges, faculty members were stunned a few years ago to discover that some students were using the same high-end calculators required for many advanced math tests to retrieve stored information during exams.

But the use of cell phones "was a new one for us," said John Zacker, the university's director of student discipline.

The accusations prompted university administrators to send a memo to faculty members yesterday advising them to monitor the use of cell phones and other electronic devices during exams.

The incident also highlights an apparent generation gap in technology savvy on campus. While students by and large expressed no surprise that cell phones could be used for illicit purposes, Zacker said it simply had not occurred to most faculty.

Zacker said the accused students are suspected of exploiting a common practice at College Park, in which professors post answer keys outside their offices after giving an exam so that students can immediately calculate how they did.

Some professors, he said, have gotten in the habit of posting the keys while students are still taking the exam, assured that students would not be able to see the answers until they had turned in their tests and left the proctored classroom.

It is unclear exactly how the accused students may have cheated, Zacker said. But preliminary investigations suggest that they may have arranged to have friends outside the classroom consult the keys and call in the answers.

In some cases, professors had posted answer keys on their Web sites, and officials believe that students may have used cell phones equipped with Web browsers to look up the answers themselves, while still in the exam room.

The memo, from Provost William W. Destler, also advised faculty not to post answer keys until well after an exam is completed.

Zacker would not say which professors or departments had reported the recent accusations or whether all 12 cases came from the same course.

The University of Maryland has worked to bolster a culture of academic integrity in recent years, including the institution of a new honor pledge that students are urged to sign on their work. The student-run Honor Council will rule on the cases in coming weeks. First-time offenders at Maryland generally receive a failing grade for the course with a marker on their transcripts indicating that cheating was involved, but additional offenses can merit suspension or expulsion.

Donald L. McCabe, a professor at Rutgers University who has studied academic dishonesty, said he had heard of other instances of students across the country using a cell phone to cheat.

Though technology has made it easier for students to cheat -- and possibly harder for professors to detect it -- McCabe does not believe that it has tempted more students to cheat. However, he said it may have increased "the frequency with which cheaters cheat."

"Ten years ago, you'd hear about students using hand signals or tapping with pencils on their desk," he said. "Things like this are displacing that. You don't have more cheaters, just more ways to cheat."