Hi, Bucko,
Hopefully this attachment works and here are some simple instructions.
I'd cut the outside edge of this tooth shape in 3/4" wood of choice and two (2) more of the same shape from 1/4" material.
(The two 1/4" pieces are the top and bottom of the box and the 3/4" piece is the side walls of the box.)
Now cut the inside area of the 3/4" tooth which I designated with a dashed line.
Trace the inside area of the 3/4" tooth onto 1/8" or 1/4" wood and cut that shape out. I call this the lip that fits into the box side-wall.
Make sure that 1/8" or 1/4" material fits into the cut out area of the 3/4" inch tooth. A slightly loose fit is best so that it will go onto and come off of the 3/4" tooth easily.
Lay the 1/4" top on your work area up-side down (best surface down on your work area), align the side-wall 3/4" box onto the top, glue the 1/8" or 1/4" lip onto the top of box making sure not to glue the top or lip onto the side-wall.
Now align and glue the 1/4" bottom onto the side-wall.
Now, if desiredd, you can paint the entire box white and then trace the smiley face and paint it onto the top of the box. If you don't like the idea of painting the face, you can print the smiley face on standard paper and glue it onto the top of the box.
I hope this is helpful to you and would like to see the project if you decide to use it.
God Bless! Spirithorse