Yohaku Puzzles

As educators, we know that to have effective mathematics instruction, we must promote mathematical problem solving while encouraging discourse (NCTM 2014), yet finding tasks that both challenge and engage students can be difficult. We discovered that the Yohaku, a Japanese number puzzle, provides a format that was both challenging and thought-provoking when implemented in a secondgrade class in a Virginia elementary school. The number puzzle involves having students fill in squares with numerical values such that each column and row creates the same value. We discovered that students enjoyed the puzzle and that it supported their own construction of number sense.