From nationalmerit.org
Winner Selection
"A variety of information is available for NMSC selectors to evaluate?the Finalist's academic record, information about the school's curricula and grading system, two sets of test scores, school recommendation, information about the student's activities and leadership, and the Finalist's own essay. All winners of Merit Scholarship® awards (Merit Scholar® designees) will be chosen from the Finalist group, based on their abilities, skills, and accomplishments."