A wrapping band for converting cut standard food cartons into a toy building block, which in the form of a continuous band comprises five surface elements. Each surface element is hinged to the adjacent element or elements along a line or lines, perpendicular to the longitudinal direction of the band. The surface elements are connected as follows: a first end element having a closure slot for engagement with a closure tongue; a top element having a plurality of circular projections or pegs; a second end element; a bottom element having a plurality of holes corresponding to the number of pegs in the top element; and generally arrow-shaped locking tongue for engagement with the slot. The toy building block is formed when the band is secured about the carton.
