Courses
One idea, taken all the way up.
A course walks one territory from first principles to competition strength - short lessons name the idea, then the problems climb. Every step is tracked.
3 courses · 106 problems
Plane geometry IThe full toolkit of the first rounds - congruence, measurement, circles and vectors, in forty problems.4 chapters · 40 problems · 10 lessonsStart the course →Plane geometry IISimilarity, circles at work, and the triangle's centres - the geometry of the regional rounds.3 chapters · 33 problems · 2 lessonsStart the course →Plane geometry IIIThe national rounds: sustained angle chases, transformations, and the incircle's whole family.3 chapters · 33 problems · 2 lessonsStart the course →
UpcomingAlgebra, number theory, combinatorics, and logic and sets are being prepared - their problems are already in the practice library.
Lessons and problem statements are open - sign in to track progress, open hints, and read solutions.