She also works in the school's main office and counselor's office, spending the second of the school's four blocks handling office work.
After school, Cox manages to squeeze into her busy band schedule of activities 15 hours a week to work at $6 an hour at the Food Lion grocery store and time to take clarinet lessons.
But her dizzying day is not over.
At home, she serves in the role as housekeeper, helping out her mother, Cyndi Cox, who has cancer. She also tends to the needs of her self-employed father, John Cox, whose heating and air conditioning business keeps him working long hours, and she takes care of her little brother.
At church, she is the leader of the youth group and the youth band.
"It's extraordinarily difficult to balance everything I do, but everything is either something I need to do or want to do, so it has to get done," said Cox, taking a break from her high school office job to talk about her busy life.
Finding ways to manage it all
While not leading quite a breathlessly busy life as Cox, many of her senior classmates also must find ways to manage their time to accommodate school work and after-school jobs as well as their home lives and social lives.
Ryan Funkhouser works 30 to 35 hours a week at the Western Sizzlin at $6 an hour. He uses his paycheck for "extra spending" money. In addition to his job and school work, he also plays baseball.
"I have to manage my time, but it hasn't been real hard," said the son of Becky Bandura and Tom Funkhouser, who started his steakhouse job a year ago. "My parents are OK with it. It was my decision and I'm glad I made it."
Funkhouser said he has been able to devote enough time to his studies to maintain good grades.
"In the spring, when I'm playing baseball, I don't work," he said. "That makes sure I can handle my school work."
For Jason Claude, fall is the busy time of year. The son of Andrea Page is a member of the DHS football team. Like Funkhouser, he doesn't work when his sport is in season.
But after the Admirals have hung up their helmets, usually in early December, Claude puts on a McDonald's cap and works 30 to 35 hours, four days a week at the fast-food restaurant. He is paid $5.50 an hour, calling his pay "spending money."
"I don't think I could work and play football at the same time, because football's almost a full-time job itself, with all the practices, film sessions and games," he said. "But I am able to handle the McDonald's job and school when football is out of season.
"My mom's fine with me working, as long as I get my school work done, and I've been able to do that," Claude said.
Covering car expenses and paying for "special things"
Dazzmine Cobb puts in 30 hours a week, at $5.25 an hour, at the Sonic Drive-in. She uses the paycheck to cover car expenses and to pay for "special things" such as her senior photos.
"It's kind of tough sometimes to get everything done," said the daughter of Canisha Berry and Keith Averitt. "I also go to night school here at the high school 4 to 7:30 two nights a week, and I play powder puff football.
"But I need the money from the job to pay for things I need to have," said Cobb. "As long as I get my school work done, my parents are OK with me working, and I'm OK with it."
Every cent of the $5.25 an hour that Carmelita Ashley Andrew earns at her 25-hour-a-week job at Krystal's is necessary. No play money for her.
"I need the money to cover my car expenses and also to help with the family budget," said the daughter of Carmelita Andrew and Charles Andrew. "My parents would rather I not work and focus totally on my studies. But I need to work, for me and for my family."
In addition to her academic work and job, Andrew also is a member of the DHS marching and concert bands, throws the shot put and discus on the Admirals' girls' track and field team and is a leader of her church's youth group.
"Sometimes I'm so busy, I don't get through with my homework till real late. Sometimes, I don't get to sleep until 1 or 2 in the morning," she said. "But you have to do what you have to do, and I'm doing what I have to do, and also what I want to do."
A certain classmate of Andrews knows exactly what she's talking about.
"With a busy schedule at home, school, work and church, you can get worn out," said Ashley Cox. "But as long as I stay healthy, I'll keep doing it."
And Cox makes a special effort to stay healthy. Add one more activity to that already long list.
"I go to a local gym and work out," she said. "I really don't have the time but I make the time. If I'm not healthy, I couldn't do everything else on my list."