Successfully implementing the practice of inclusion by differentiating instruction is dependent upon both the skills and attitudes of general education teachers. New general education teachers who are entering the field are particularly vulnerable to the demands and stress of the profession, and exemplary preservice teacher education programs must prepare preservice teachers to meet the needs of all students by giving them the skills to make appropriate lesson adaptations, accommodations and modifications. This study investigates the manifestation of differentiation for special education students in work sample lesson plans written by preservice teachers working toward an elementary school credential. The research examined the nature, characteristics, and types of instructional adaptations included in the work samples prepared by a sample of preservice teachers. Six themes surfaced from the study of the categorical data and the text taken directly from the lesson plans in the work samples. First, no evidence of purposeful planning for students with Individual Education Programs emerges in the sequence of the lesson plans. Second, accommodations written into the work sample lessons center around partner or group work. Third, preservice teachers have an undeveloped or inaccurate understanding about special education and its terminology. Fourth, preservice teachers tend to use multiple intelligences and the use of manipulatives for differentiation. Fifth, preservice teacher reflections focus on the teacher rather than student learning. Sixth, very little evidence of meaningful planning or differentiation for students with disabilities appears in the work sample generally. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]