Illinois Central College's Development of Operational Reasoning Skills (DOORS) project, which is based on Piaget's developmental theory and learning cycle strategy, is described. The project provides a multidisciplinary freshman core program focusing on the improvement of student reasoning abilities. For each of the six DOORS courses--English, mathematics, physics, history, sociology, and social science--several major thinking skills were identified, and all the classes emphasize the same skill at the same time in the semester. Pretesting and posttesting of students to assess changes in cognitive skills and other defined parameters were undertaken. The initial assessment was based on collected high school grade point averages, graduating class rank, and reported American College Testing Program scores. Using a test developed to assess cognitives skills, evidence was found that DOORS students were less academically prepared than the typical entering freshman at ICC. To evaluate the success of the DOORS program in altering the normal attrition of students from college during their first semester, comparisons were made of grades and attrition frequencies for specific courses. Despite several problems in the evaluation process, the results seem to suggest that DOORS students make as much intellectual progress as a typical group of community college students, and do so with significantly lower attrition. The program has allowed six instructors the opportunity to investigate thoroughly the use of experiential learning techniques. Student evaluation of the program was undertaken by administration of a questionnaire and through written descriptions of student impressions, some of which are appended. (SW)