For students looking to practice with past papers, several high-quality collections are available in digital format: Cuban Mathematical Olympiads (2001–2016) : This definitive book, available at the AMS Bookstore AwesomeMath
: The problems cover four main pillars of contest mathematics:
To find updated resources, I recommend checking the following:
that includes problems and solutions from the 2023 National Olympiads for both middle and high school levels. Cuban Mathematical Olympiads (2001–2016) : Published by AwesomeMath
Typically held over 2 consecutive days, with 3 problems per day. Time Limit 4.5 hours per session.
: Divisibility, integer solutions, and modular arithmetic.