Toy Building Block

FIG. 1 is a perspective view of a toy building block showing my new design;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a front elevational view thereof; and,

FIG. 5 is a bottom plan view thereof.

Portions of the article shown in broken lines form no part of the claimed design.