Problem-solving journal

A problem journal records not just the answer but the path to it, including the wrong turns. It follows the four phases George Pólya set out in How to Solve It: understand the problem, devise a plan, carry out the plan, and look back. The last phase is the one most people skip, and it is where the lasting value is: the technique you will reach for next time.

Experienced problem solvers keep such journals because solutions are easy to forget and techniques are reusable. A good entry lets you, months later, see not just what the answer was but what made it findable.

When to use it

• Someone is working through competition problems (AMC, olympiad, Putnam), puzzle books, or coding puzzles.
• They are stuck and want to lay out what they know and have tried.
• They solved something and want to capture the insight before it fades.
• They are building a personal collection of techniques.