When I was operations manager on the original version of TIC TAC DOUGH, I designed a huge cabinet with countless shelves to store all the category cards to load into the game board. With that in mind, I thought I could do the same with CONCENTRATION. At first, I really did consider storing the often used symbols, such as drawings of oars, eyes, bees, capital letters, etc and etc. I quickly gave up on that, there were too many variations of size ---like a drawing in 1, 2 or 3 squares, with or without plus signs, and the multitude of different clues. It was cheaper, faster and more realistic to make each puzzle an original work of art.