The monthly cost is a fixed $8 to $12, depending on options, which makes it less expensive than a cellular phone, which is billed by the usage.
Alpha numeric pagers, which display personal messages, are more expensive.
Parents like the ability to have their teenagers at their beck and call, said Sean Marriner, owner of Quantum Communications in Hagerstown.
For the teenagers, it is kind of a status symbol.
However, pagers are illegal in Maryland schools, said Andrew McMahon, assistant to the superintendent of the Washington County Board of Education.
Few students break the rule because of the strict punishment - expulsion.
At Hedgesville High School, Geary and her friends are allowed to carry pagers as long as they are switched from beep mode to vibrate mode.
"If one goes off in class, people are all looking at their pagers," Geary said.
Most of Geary's pages are from friends. Sometimes they use the beep as a signal to meet at the mall, she said.
One time, a boyfriend paged her 14 times in one hour, she said.
When she is babysitting 4-year-old twins Jacob William and Jordan Elizabeth, Geary is in constant touch with their parents.
Camilla and Kevin Mills of Falling Waters, W.Va., can beep her whenever they want to check up on the twins.
Geary can also beep the Millses, whose pagers are connected so they receive the same messages.
Jacob has asthma, so babysitters are instructed send a page before he gets any medicine.
"I like to know these things," said Camilla Mills, who works at Shenandoah Business Systems in Martinsburg, W.Va., and has gotten pagers for all her babysitters.
Recently, when the twins were at the fair with another babysitter, Camilla Mills was able to page them to find out why they were running late.
"Had that not happened, I probably would have gotten in my car, driven to the fair and looked for them," she said.
Pagers are getting more specialized, Marriner said.
The most recent novelty is sports pagers, which display updates on Major League Baseball games every 30 seconds, he said.