1. A computer-implemented method for providing individualized essay writing instruction, the method comprising: receiving an essay in an electronic format using a computer; automatically determining with the computer a first value for each sentence in the essay that reflects the probability that the sentence is a member of a discourse element category, wherein the probability is based on the presence of each of a predetermined set of features in the sentence; utilizing the first value to determine with the computer whether each sentence in the essay should be assigned to a discourse element category; identifying with the computer any discourse elements in the essay; if the first values do not indicate the presence of a discourse element in the essay, indicating that the essay lacks sufficient clarity; generating feedback regarding the presence or absence of discourse elements in the essay; and transmitting the feedback for display to a user.