CUT corners off 10 grahams for the fronts and backs of the 5 houses.
SPOON frosting into resealable plastic bag. Cut small piece off one bottom corner of bag. For each house, use 1 graham for the floor, 2 whole grahams placed horizontally for the side walls and 2 cut grahams placed vertically for the front and back walls, using some of the frosting to attach all graham pieces together. Use additional frosting to attach 2 grahams to top of each house for the roof. Cut chocolate graham into pieces and attach to houses for the doors.
CUT remaining grahams as needed for the chimneys, angling 2 pieces for each chimney and attaching with frosting. Let houses stand at least 3 hours to dry.
DECORATE with remaining ingredients as desired.