"It's like winning the lottery," said Helen Wiersma, of Okeechobee, Florida.
The top winner will receive $100,000. Intel is spending a total of $1.2 million on the awards.
The finalists are gathering in Washington, D.C. for the announcements.
This contest has a prestigious track record. It's produced five Nobel Prize winners, and more than 90 percent of the students go on to a career in science.
Seventeen-year-old Lucas Hanft chose to explore the social sciences - by devising a project to test New Yorker's honesty.
He intentionally lost pieces of mail - in phone booths, coffee shops, even near parked cars. The result - more than half his letters were mailed back - giving him a new research tool, and making him, a finalist.
"I don't really think I have that great a shot. These people here are so brilliant that everybody deserved to be top ten," said Hanft.
Finalist Kristin Kovner of Port Washington, NY concurs. "I sit back and my eyes are wide open at the knowledge these people possess. Some kids know more about my project than I do."