Using basic Euclidian solids, I explain that you can represent anything in the world.  Knowledge of these basic two-dimensional shapes also happen to be a part of our Preschool Math curriculum.  

Below you can find a template to make the stencils you will need to set your children to work on the shape alphabet project.  I trace each shape in pencil on construction paper, and allow each child to cut it out to the best of their ability.  Children who are still working do refine their fine-motor skills will benefit from using a thicker stock of paper.  

Find here the Stencils to use for each letter

Using my piece as a exemplar, they paste each shape to their paper as best they can.  I have them use paste and apply it with a paintbrush.  Glue sticks, I have found, do not work well.  I have also been told by an Art teacher that children should only apply glue with a brush, but I do not know her reasoning. 

After the pieces have dried, I have them laminated for perpetuity, and displayed on the classroom bulletin board.