Michael Rosenman, 16, of Georgetown Day School and Elizabeth Lacovara, 15, of Georgetown Visitation have spent most of this summer helping researchers in the pathology department at the National Zoo conduct tests on blood and tissue samples of dead or infected animals.

At Howard University's Cancer Center, Sean Jenkins, 16, of Archbishop Carroll High has been testing the effects of proteins on human organs by measuring protein counts with a spectrophotometer. Seralyn Pink, 16, of Benjamin Banneker High, worked with bacteria cultures at Howard's Medical School.

All four students are among 26 sophomores and juniors from District high schools chosen to participate in the American Cancer Society's 20th annual summer science research program at 11 medical and research institutions throughout the Washington area.

Named the Kathrine Dublin Folger Scholarship Program after one of its founders, it was established in 1963 by the District chapter of the American Cancer Society, to "expose and motivate students to pursue a career in the field of science," said spokeswoman Lois Callahan.

Each spring, science teachers in District public, parochial and private high schools choose five top science students to compete for the 26 positions in the summer program. Finalists are chosen partly by performance on a standard science achievement test. The 26 scholarship recipients are awarded a stipend of $225 each for meals and travel expenses, according to Callahan.

I've always had an interest in research and this was an opportunity to find out just how interested I am," said Rosenman. "Research is a lot of hard work and it's not just 'Eureka!'--discovery after discovery--but it's worth it."

Rosenman and Lacovara, who said the highlight of the summer was witnessing the autopsy on giant panda Ling-Ling's offspring, both said they are undecided about what college to attend next year and about career choices. But they said the summer program provided a chance to take a closer look at the health professions.

"This program has helped me decide to make medical research a real possibility for a career," said Jenkins.

Pink, after running tests on the bacteria cultures, photographed her findings with the medical mycology department's $175,000 electron microscope and transmission microscope.

"I did the summer program for the experience. This gives me the chance to explore different areas for a possible career," said Pink, who is considering a career in agronomy, the science and economics of crop production.

"When I first arrived here at the zoo I must have driven the mentors crazy with questions," said Lacovara. "The mentors here seem to want us to get something out of the program, not just a little knowledge but an attitude that would enable us to like and remember what we did this summer."

Of the 26 students selected from 60 applicants for this year's program, only two are from public schools, a pattern the selections have followed from the program's beginning.

"The public schools are competing with private and parochial schools, which are very competitive," said Deborah Smith, coordinator of the summer program. "We have a difficult time getting the public schools interested enough to send kids to even try for the program."

Dr. Lena Austin, a medical mycologist who is Pink's mentor at Howard University Medical School, said she specifically requested that a public school student be assigned to her for the summer.

"The students from Sidwell Friends and many of your other private schools will probably have a chance in life," said Austin. "I worry about the ones we miss, which are usually the ones in the public schools."