Ready to Grow Progressive Puzzle sets include 5 different puzzles of varying complexity. Each puzzle has a uniquely-colored background and border to aid in sorting the pieces, a first step in completion. The step-by-step mastery of the simpler puzzles encourages children to meet the challenges of increasingly difficult puzzles, building confidence and creating a sense of accomplishment. This set contains a 3, 4, 6, 9 and 12-piece puzzles. Completed puzzles are approximately 8” wide in size.