The main aim of this research was to improve a blended learning course, by adding specific online activity that will improve learning outcomes and enable producing, collecting and analysing educational data. Moodle LMS, a widely used, well-known learning environment, was used for realisation of the online activity. Data collected over LMS Moodle was analysed by using Big Data technologies to find out performances and check learning outcomes in the extended blended learning system. Over 600,000 records generated by students and teachers during the three schoolyears were collected as a part of this research. The total number of activities, type of activities and their correlation with the final grade on the course have been observed and analysed. Research results show, that by introducing only one mandatory activity -- online discussion, the number of all activities and the number of aimed activities have been increased significantly. More frequent and numerous access to educational content increased the number of students who passed the final exam and increased the average grade. The research was conducted at the Academy of Technical and Art Applied Studies Belgrade, Department School of Electrical and Computer Engineering on the course Social Networks Analysis.