The ornamental design for a lawnboardgame, as shown and described.
FIG. 1 is a front and top perspective view of the lawn board game, showing our new design;
FIG. 2 is a front view of the design illustrated in FIG. 1;
FIG. 3 is a rear view of the design illustrated in FIG. 1;
FIG. 4 is a top view of the design illustrated in FIG. 1;
FIG. 5 is bottom view of the design illustrated in FIG. 1;
FIG. 6 is right side view of the design illustrated in FIG. 1; and,
FIG. 7 is a left side view of the design illustrated in FIG. 1.
The uneven broken lines in FIGS. 1-7 represent the bounds of the claimed design, and the regular broken lines represent unclaimed portions of the design. The broken lines form no part of the claimed design.