The Science Talent Search and scholarship program has been in existence since 1942. It is currently sponsored by Regeneron, and was sponsored by Intel before that and Westinghouse before that. The program seeks high school seniors who have done independent research, and there are many scholarships available from $2000 awards to 300 students all the way up to $250,000 for the top scholar!
Application deadline is November 15, 2017. For more information and to see a sample application: