Samantha Garvey is one teenage girl who would rather read something called The Journal of Shellfish Research than Glamour magazine. "What I'm doing is the American dream," she says. The 17-year-old high school senior maintains a 3.9 grade point average at her Brentwood, N.Y., high school, studies Italian and plays the violin. She also has an unusual interest that has recently caught some attention: On Wednesday she was named one of 61 Long Island semifinalists in the national Intel Science Talent Search because of her work studying the effects of predators on ribbed mussels. "I get so excited to tell...