25-piece jigsaw puzzles.
Starting to think strategically.
Twenty-five pieces in a 5×5 grid — about six minutes. At this count you'll naturally start sorting pieces in your head before placing them, which is where puzzle-solving stops being trial-and-error.
About 25-piece puzzles
Twenty-five is where the technique starts. Instead of grabbing whichever piece happens to be on top, you'll find yourself scanning the available pieces for a colour zone, building two or three small islands, then bridging between them. It's still a comfortable session — under ten minutes — but the mental work feels meaningfully different from sixteen.
This is also the count we recommend for older players who want a daily ritual without strain. Twenty-five pieces is large enough to enjoy on a tablet, small enough to finish in a single sitting, and the difficulty doesn't depend on small details.