This is the better version of the one that I was going to make. First version had a tile for each number. For this version a slider is placed over the numbers to show the right numbers in that month.
The font I used this project is Daisy by Richard William Mueller
Craig http://www.thingiverse.com/builttospec cut the wood for me with his laser cutter.
.25 oak plywood was used for the cut and the drawings are to that thickness. Edit files for your wood thickness.
Stain or paint the cut wood. If you use a nice hardwood plywood use a good stain.