The aim of the study is to determine the impact of online learning activities on learning outcomes of students who participated in the blended learning course, focusing specifically on skill-based courses. The learning outcomes or results of a learner are usually measured by scores, knowledge or skills gained in the course. In blended learning courses, the learning outcomes can be assessed according to many criteria. In this study, interactive activities such as teacher-student interaction, student-student interaction, student-content interaction and student-technology interaction are considered. Undergraduate students participated in the blended learning course in which formative assessment was used to evaluate student learning outcomes by the combination of different learning activities through a learning management system. The quantitative results obtained by using regression analysis of data from the system showed that the students who effectively interacted with learning activities in the course have better results. Quantitative analytical results indicated that student-student interaction has a greater impact on student learning outcomes. These learning activities are used for interactive activities as suggestions for teachers to design and implement learning activities for blended learning courses. 2017 World scientific publishing co.