Master these mathematical crosswords that combine logic with arithmetic. Kakuro grids contain clues (sums) for horizontal and vertical runs of cells. Fill cells with digits 1-9 (no repeats within a run) that add to the given sum. Start with small puzzles to learn common number combinations (17 in 2 cells must be 8+9), develop elimination strategies, and recognize patterns.
Kakuro exercises mental arithmetic, logical deduction, and pattern recognition more than calculation—you're figuring out which numbers fit, not computing sums. Difficulty ranges from easy to extremely challenging. Free puzzles online at puzzle sites and daily newspapers.