Counted that I have enough white sraperboard for an additional 400 pages. I need to get at least 3 full packages more. For drawing I'm using textmark markers, haven't found anything better. They wear out relatively fast so I'm using approximately 20 in a month. The project requires 3 more years. 12 x 3x 20 equals 720. I collect the used markers to a plastic bag beside my desk.