Story highlights Samantha Garvey lives in a homeless shelter and attends a Long Island high school

She is one of 300 semifinalists in prestigious Intel Science Talent Search competition

She'll find out soon if she's one of 40 scholars who will travel to Washington

Her father describes her as "a hard worker, very driven and dedicated"

For two and a half years, Samantha Garvey has immersed herself in New York's Long Island salt marshes -- prodding, examining and questioning, all in the name of science.

But after a hard day's work, at school or in the field, the high school senior hasn't been able to head home at night. That's because she doesn't have a home.

The 17-year-old has not let living in a homeless shelter deter her from her dreams. On Wednesday, she was named one of 300 semifinalists in the prestigious Intel Science Talent Search, putting her in contention to earn a $100,000 college scholarship.

"She is very special," her father, Leo Garvey, told HLN's Jane Velez-Mitchell on Thursday night. "She's a hard worker, very driven and dedicated to anything and everything that she does."

Along with her studies at Brentwood High School, situated about half the length of Long Island some 45 miles east of New York, Samantha Garvey has spent much of her spare time working with marine biologists.

That led to her project, which according to the Society for Science and the Public website is titled, "The Effects of Physical Environment and Predators on Phenotypic Plasticity in Geukensia demissa." For those who aren't high school science wizards, this translates to how ribbed mussels -- the common term for Geukensia demissa -- adjust their characteristics, or phenotypes, in response to predators and the world around them.

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The odds were stacked against Garvey when she submitted her effort for the competition, given that 1,838 others from 500 high schools had also turned in applications. When she learned she made the first cut, the high school senior said she was in "complete disbelief."

"I was absolutely ecstatic," she told HLN. "It's the most amazing feeling. You can't believe it's happening."

Progressing further may not be much easier. For one, the competition has a tradition of soliciting projects from some of the nation's top young scientific minds: Previous participants in the program have won seven Nobel Prizes and 11 MacArthur Foundation Fellowships, among many other honors, according to the contest's website.

All those selected as semifinalists, including Garvey, will get a $1,000 award. The 40 finalists will be selected from that pool and announced on January 25. They will all earn a trip to Washington, D.C., where last year's finalists met with President Barack Obama and other officials, and earn scholarships ranging from $7,500 to the top $100,000, according to Intel.

Whatever happens with this competition, Garvey said she has high hopes for the years to come.

That includes attending college at either Brown or Yale, she says, and ideally someday landing a job with a government agency like the National Oceanic and Atmospheric Administration.

"I have a lot of plans for the future," Garvey said. "I'd like to continue what I'm doing now -- continue with science research and just get a doctorate and keep on trucking."