The book emerged from the authors’ experience coaching the US International Mathematical Olympiad (IMO) team. It is a beginner’s problem set—it’s designed for high school students already comfortable with standard algebra who want to advance to olympiad-level problem solving.
Among purely problem collection books, “101 Problems” is more concentrated and harder than AoPS Vol 2’s algebra sections but less comprehensive in theory.
: Each problem is hand-selected to teach a specific technique.