Introduction The problem of learning disabilities is a world problem that is not limited to childhood or the school side, but extends to the next life of the individual, Learning disabilities are represented in the existence of a discrepancy between the student's expected performance according to his mental abilities (average intelligence level or more) and his actual performance as expressed in achievement tests in one or more subjects, Science learning disabilities are among the academic learning disabilities that have not received sufficient attention compared to other academic disabilities such as reading, writing and mathematics, although many students find it difficult to learn science, and this difficulty increases in the case of students with learning disabilities, we also find that science learning disabilities are among academic learning disabilities that impede students’s learning and academic performance, not only in science, but in other subjects, Science is one of the most important subjects for students with learning disabilities; where many studies indicated that science helps in integrating these students into the educational process by encouraging them to participate in various educational activities that depend on the use of materials from the environment and appropriate laboratory tools. Differentiated instruction is one of the educational strategies for remedial instruction that has proven effective in learning students with learning disabilitie, it is a student-centered educational strategy; where each student is taught according to his individual needs, abilities, past experiences, interests and learning preferences and this includes take advantage his strengths, which helps to reduce the Summary 2 shortcomings that he suffer from it, we find that many studies have confirmed the low academic achievement and level of performance of students with learning disabilities in Prep – School compared to their normal peers in the subject of science, such as the study of Barabasz (2018), McGrath & Hughes (2018), and Kaldenberg et al (2015), and studies have also indicated the effectiveness of differentiated instruction in learning science curricula to students with learning disabilities in different educational stages, including Prep–School, such as the study of Liverman(2014), Simpkin et al (2009), Olsen (2007), so this study sought to study the effectiveness of the differentiated instruction strategy on reducing science learning disabilities in first preparatory stage students. Problem The problem of the study is represented in the following main question : “What the effectiveness of differentiated instruction strategy on reducing science learning disabilities in first preparatory stage students?”, and there are some questions derived from this main question: 1 – Are there statistically significant differences between the mean scores of the experimental and control groups in post test of the symptoms of science learning disabilities, in favour of experimental group (in the best direction)?. 2 – Are there statistically significant differences between the mean scores of the experimental group in pre and post test of the symptoms of science learning disabilities, in favour of the post test (in the best direction)?. 3 – Are there statistically significant differences between the mean scores of the experimental group in the post and follow up test (after two months) of the symptoms of science learning disabilities?. Aims The study aims to reduce science learning disabilities in first preparatory stage students through the preparation and application of a remedial program based on Summary 3 differentiated instruction strategy, and testing the effectiveness of the program and the extent of its impact during the follow-up period. Importance Reducing science learning disabilities in first preparatory stage students through remedial instruction program using differentiated instruction strategy. Terminology 1 – Learning Disabilities (LD) 2 – Science Disabilities 3 – Differentiated Instruction 4 – Effectiveness 5 – Remedial Program Participants This study has been carried on a sample (14) student from science learning disabilities students in first preparatory stage, with average (12,7) year, and standard deviation (0.83). They were divided into two matched groups; experimental (n=7), and control (n=7), and the sessions of the treatment program used in the study were applied to the students of the experimental group, and the number of sessions reached (32) sessions, and the application took two months, with four sessions per week. Tools 1 – Stanford-Binet Intelligence Scale – fifth edition – (arabization of Safwat Farag, 2010). 2 – Achievements tests in science for first preparatory stage 3 – Quick Neurological Screening Test (QNST) (prepared by Margaret Moti et al, arabization of Mostafa Kamel, 2007). Summary 4 4 – Diagnostic Scale for symptoms of science learning disabilities in first preparatory stage students (prepared by Prof.Dr. Adel Abdulla, Alshimaa Abdeldaim). 5 – Remedial Instruction Program using differentiated Instruction Strategy (prepared by Prof.Dr. Adel Abdulla, Alshimaa Abdeldaim). Statistical Techniques The researcher used some statistical methods to process the data and test the validity of the hypotheses, which were as follows: 1 – Mann – Whitney test. 2 – Wilcoxon Signed Ranks Test. 3 – Z value. Results 1 – There are statistically significant differences between the mean scores of the experimental and control groups in post test of the symptoms of science learning disabilities (dimensions, the total score) in favour of experimental group (in the best direction). 2 – There are statistically significant differences between the mean scores of the experimental group in pre and post test of the symptoms of science learning disabilities (dimensions, the total score) in favour of the post test (in the best direction). 3 – There are no statistically significant differences between the mean scores of the experimental group in the post and follow up test (after one month) of the symptoms of science learning disabilities (dimensions, the total score).