The 300 semifinalists were selected from 1,608 entrants in Intel Science Talent Search were announced Wednesday afternoon.
20 % of this year's national semifinalist came from long Island high school and 11 lead student prize-winners with Setauket's Ward Melville High School.
Each win $1,000 in this preliminary round, and their schools are awarded equal amounts, resulting in $600,000 in total awards.
On January 28, 40 finalists will be named. They will receive an all-expense paid trip to Washington, D.C., in March to compete for more than $500,000 in prizes.