The aim of this study is to determine effects of the project-based learning approaches on Social Skills, Academic achievements and Problem Behaviors of students studying at 3 rd grade primary school with Mild Intellectual Disability (MID) in sciences course. The participants of the research consisted of 10 students in Karamanoğlu Mehmetbey University from the Faculty of Education Integration Unit Pupa in 3 rd grade. In the study, pretest-posttest design, one group of pre-trial model, was used. To the students at the study, The Social Skills Rating System (SSRS) developed by Gresham and Elliot (1990) pretest -posttest was applied. SSRS, social skills and behavior problems that are considered to be associated with these skills of preschool and elementary school students was developed in order to determine their academic qualifications. In SSRS, there are three separate scales: Social Skill Scale, problem behavior subscale and academic achievement scale. To the students in the study, "I and my environment" topic was tauhgt with Project Based Learning Approach (PBLA) for 3 weeks, and the significance of the scores obtained by applying the scale before and after the course was examined. The data were analyzed by using rank test signed non-parametric Wilcoxon on SPSS 16.0 software. At the end of the study, while there was a significant relationship between the scores of the participants' social skills based on the project-based learning approach, there was no significant correlation between problematic behavior scores. Furthermore there was also a significant difference between the scores of participants' academic competence. As a result, it can be said that the course tauhgt with PBLA improves social skills and academic achievement of students with MID. Despite the decrease in the problematic behavior scores of the students, no significance was observed.Keywords: Project-Based Learning; Mild Intelligence Disability; Social Skill; Academic Efficacy; Problem Behavior.(Extended English abstract is at the end of this document) ders öncesinde ve sonrasında ölçek uygulanarak elde edilen puanlar arasındaki anlamlılığa bakılmıştır. Puanlar SPSS 16.0 programında non-parametrik Wilcoxon işaretli sıralar testi kullanılarak analiz edilmiştir. Çalışma sonunda proje tabanlı öğrenme yaklaşımı ile işlenen ders neticesinde katılımcıların sosyal becerilerinin puanlarının arasında anlamlılık bulunurken, problem davranış puanları arasında anlamlılık bulunamamıştır. Ayrıca katılımcıların akademik yeterliliklerine ilişkin puanlarının arasında da anlamlılık görülmüştür. Sonuç olarak proje tabanlı öğrenme yaklaşımın hafif düzeyde zihinsel engele sahip öğrencilerin sosyal becerilerine ve akademik yeterliklerine olumlu katkısının olduğu söylenebilir. Öğrencilerin problem davranış puanlarında ise azalma olmasına rağmen anlamlılık bulunmamıştır.