Puzzle

A children's puzzle including a rigid frame and a set of removable, rigid, noninterlocking pieces. The rigid frame has two opposite broad sides defining a thickness therebetween. Each broad side of the rigid frame defines multiple recesses therein. At least one of the recesses on at least one broad side of the rigid frame is configured to loosely contain multiple pieces of the set. The recesses of each of the broad sides of the rigid frame are sized to simultaneously accommodate all of the pieces of the set and are arranged differently, so as to form respective arrangements of the pieces of the set when accommodated in the recesses. The set of removable, rigid, non-interlocking pieces each have a flat bottom surface. At least three of the pieces have different perimeter shapes. The pieces of the set are configured such that when retained within the respective recesses, they are retained only by gravity.