drawing board 
noun
A large flat board on which paper may be spread for artists or designers to work on.Since most of modern wars are fought less on the field and more on the drawing boards with paper and pencils, a lot of papers have been flying around....
- With the rain keeping away for the day, the children, armed with drawing boards, paint, brushes and palettes, waited patiently for the 2002 edition of the competition to commence.
- My designs have never got past the drawing board.
Phrases
back to the drawing board
on the drawing board