1. A method for computationally distinguishing hand-written marks from pre-printed artwork in a response sheet marked with pre-printed elements and hand-written elements, comprising: scanning a sheet containing only pre-printed elements to generate a first classification pixel file; identifying one or more connected pixel groups from data corresponding to the first classification pixel file; computationally detecting one or more features of the connected pixel groups of the first classification pixel file, and storing the detected features of the connected pixel groups of the first classification pixel file as a first classification set; scanning a sheet containing only hand-written elements to generate a second classification pixel file; identifying one or more connected pixel groups from data corresponding to the second classification pixel file; computationally detecting one or more features of the connected pixel groups of the second classification pixel file, and storing the detected features of the connected pixel groups of the second classification pixel file, as a second classification set; scanning the response sheet marked with pre-printed components and hand-written components to generate a response pixel file; identifying one or more connected pixel groups from data corresponding to the response pixel file; for each connected pixel group of the response pixel file, computationally detecting from data corresponding to the response pixel file one or more features of the connected pixel group; and computationally determining if the connected pixel group of the response pixel file corresponds to a pre-printed element or a hand-written element by comparing the features detected from the response pixel file with the features stored in the first classification set and the features stored in the second classification set.