The Journal of Problem Solving (JoPS) offers you an opportunity to test your problem-solving skills as well as improve them with challenging problems. A few examples of problems included in the JoPS are

How long would it take a ball to fall through a theoretical tunnel in the earth? (Journey through the Center of the Earth)

What is the probability that a randomly drawn chord is longer than a side of an equilateral triangle inscribed within it? (Bertrandâ€™s Paradox)

A solid half-cylinder, of radius R, and mass M is placed on its curved surface. One side is pushed down and released, what is the period of the resulting small oscillations? (Rocking Half-Cylinder)