In addition to her full-time job, Shelby Giles took on pro bono work as part of her master’s studies. (Jason Hornick for Express)

Aubrey Whitehead isn’t your typical intern. He’s 42, served nine years of active duty in the military and recently resigned from a GS-15 position at the Department of State to focus on getting his doctorate.

Now he’s interning in the University Career Services office at George Mason University and preparing to teach an undergrad class there in the fall.

“You’ve got to jump all in,” he says.

Like Whitehead, plenty of people don’t fit the traditional mold of a high school or college intern getting their professional feet wet for the first time.

The veteran
Older interns bring decades of skills to bear, even if from a different field. Robert DeNiro played one of these later-in-life career transitioners in 2015’s “The Intern.”

At his internship — required as part of his Ph.D program in educational psychology at GMU — Whitehead, a former headhunter, helps students in the career services office prepare résumés, interview, find internships and negotiate salaries. In his studies, Whitehead is interested in what factors contribute to college students’ interest in STEM (science, technology, engineering and mathematics) majors and careers.

“This internship allows me to talk to Mason students and get a better sense of some of those factors,” he says.

It’s an invaluable experience, he says, but the transition from well-paid employee to student and intern was an adjustment for him and his family.

“We made sacrifices so I could do this,” he says.

Carol Fishman Cohen, CEO of iRelaunch, a Boston-based return-to-work network, says if concerns about age or “overqualification” come up when seeking internships, candidates should emphasize that they sought the position because they can deliver results even at lower levels of seniority, and be able to better manage life outside of work with a less demanding position.

“Some hiring managers will not be receptive to this, but others will not have thought about it from that perspective,” she says.

The new-leafer
After nearly a decade of cleaning teeth, dental hygienist Brittany Holt, 30, was ready for a change.
“My goal [for] after I became certified as an assistant was to attend hygiene school and then dental school,” she says. “After a while, I lost my desire to do that.”

After going back to school for her undergraduate degree in psychology at the University of Maryland University College (umuc.edu), Holt decided to transition to a career in human resources. Her internships have helped her get a better sense of what she wants her future job to look like. Her first internship with Aflac last year wasn’t a good fit, but her new internship in human resources at the Department of Health and Human Services is looking more promising.

“It helped me figure out where exactly in the field I wanted to work, by the process of elimination,” she says. “You don’t have to get somewhere and sign on to a job and sign on to a salary and waste the organization’s resources.”

The do-gooder
No one likes to work for free, but it’s easier for a cause you believe in. Last spring, Shelby Giles, 32, was working full-time in federal consulting while providing pro bono consulting services to a nonprofit as part of a course in Georgetown University’s public relations and corporate communications master’s program

“Having worked in consulting, I definitely see a difference in working with such a cause-oriented organization versus working with other organizations,” says Giles, who did her pro bono work at the D.C. leadership nonprofit Public Allies. “It was a pleasure to work with so many passionate people.”

Having a full-time job at the same time gave her the financial freedom to take on those pro bono services, Giles notes. She has since left her old job to join Vanguard Communications, a social impact PR firm in DC.

The work experience gives students a “safe space” to explore this career path, says John Trybus, deputy director of Georgetown’s Center for Social Impact Communication, while the nonprofits get free labor.

“These organizations literally get the equivalent of $50,000 of pro bono services,” he says. “Many of these organizations don’t have the finance or staff to do that.”

The caregiver
After taking a three-year break to be home with her two small children, followed by six years of working at a “virtual law firm” startup, Emily Terrell, 38, was looking to break into the large law firm world again.

“Looking at my résumé, I have all this great experience, but it’s old,” she says.

Then a friend told her about the OnRamp Fellowship, which helps women return to the legal and financial workforce after a career break. Participating firms offer six- to 12-month paid fellowships that can lead to full-time employment if the match is a good fit. The women also receive career-development support, including coaching and online continuing education.

“When my children were tiny, I feel really lucky that I had the luxury to be with them during that time,” says Terrell, who is now completing a 12-month fellowship in patent litigation at the D.C. office of the law firm Cooley.

Cohen says many of the people who use the iRelaunch service are women who have taken a career break to care for children or family (men take career breaks for this reason, too). If companies ask about long gaps in your résumé, she recommends shifting attention back to prior relevant work experience.

“Acknowledge that you took the career break, don’t apologize, and then move on to why you are the best person for the role,” she says.

As part of an initiative with the Society of Women Engineers, seven companies are piloting re-entry internship programs for engineers in 2016, Cohen notes. The first program started in the D.C. area at Booz Allen Hamilton this month.

“We’re talking about a high-caliber, educated, experienced slew of talents,” she says.

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Regulatory science degrees help researchers think outside the lab

A transportation planning degree combines sustainability, transit and city development