Fif­teen years ago, second-​​grader Megan Kas­sick threw on a long white lab coat, slung a stetho­scope over her shoulder and pro­claimed her goal of becoming a physician.

I tor­mented my par­ents by playing doctor all the time,” says Kas­sick, now a 22-​​year-​​old senior biology major. “I still keep that lab coat in my closet.”

But Kas­sick no longer pre­tends to bring med­ical care to others. Now she’s living her dreams — trans­formed, she says, by a co-​​op in India that shaped her child­hood calling into a cru­sade to improve public health in devel­oping countries.

In June of 2010, Kas­sick went to India through the Pres­i­den­tial Global Schol­ar­ship Pro­gram, which offers com­pet­i­tively awarded grants to scores of stu­dents each year to sup­port their inter­na­tional co-​​op experiences.

She vol­un­teered at the Bal Basera Orphanage in Jodhpur, which takes care of chil­dren affected by HIV. According to India’s National AIDS Con­trol Organ­i­sa­tion, some 2.7 mil­lion Indians were living with the virus in 2008.

Kas­sick bonded with someone she now calls her “Indian sister,” a 24-​​year-​​old col­league named Bhawana, whose hus­band died of AIDS. Her story, Kas­sick says, was heartbreaking.

If I was having a bad day, Bhawana would look at me and smile, and say, ‘Megan, don’t worry about any­thing. Life is good.’ ”

Kas­sick did her best to remember her friend’s words when she got a ter­rible phone call from her brother about a month into her co-​​op. Their father had died unexpectedly.

She quickly flew home to Bloom­ington, Minn. Although spending time with her family was a com­fort, she didn’t want to forget about the chil­dren at the orphanage. Per­haps as a sign of what was in her heart, she had left most of her belong­ings behind at the home of her Jodhpur hosts, whom she calls her “second family.”

She went back to India three weeks after she’d left.

During the remainder of her co-​​op in Jodhpur, Kas­sick directed prepa­ra­tions for World AIDS Day, using it as a plat­form for HIV edu­ca­tion and aware­ness. She orga­nized ral­lies, con­ducted radio inter­views and arranged forums fea­turing promi­nent gov­ern­ment officials.

Kas­sick has two wishes for Jodhpur’s chil­dren. “I want them to receive a quality edu­ca­tion, and I want them to be healthy.”

Kas­sick has already been accepted to Tufts Uni­ver­sity School of Med­i­cine through its early-​​assurance part­ner­ship with North­eastern. When she enrolls in fall 2012, she plans to com­plete a joint degree pro­gram in med­i­cine and public health.

After med school, Kas­sick would like to combat infec­tious dis­eases with Doc­tors Without Bor­ders. She’s already mapped out a plan toward that goal.

In July, she returned to India to begin her third co-​​op, at the Advanced Centre for Treat­ment, Research, and Edu­ca­tion in Cancer at the Tata Memo­rial Hos­pital, in Mumbai, to work on a breast-​​cancer research project.

My expe­ri­ences have shown me what it’s like to work in this sort of field,” Kas­sick says. “I feel much more mature and aware of my place in the world.”