Building Block Storage Box

FIG. 1 is a perspective view of a building block storage box in a collapsed state, showing my new design;

FIG. 2 is another perspective view thereof, shown in an expanded state;

FIG. 3 is a front view thereof;

FIG. 4 is a right view thereof;

FIG. 5 is a left view thereof;

FIG. 6 is a back view thereof;

FIG. 7 is a bottom view thereof; and,

FIG. 8 is a top view thereof.

The broken lines shown on the drawings depict portions of the building block storage box that form no part of the claimed design.