Technology enhanced learning is today a part of most university courses and pure traditional face-to-face courses are rare. Modern blended learning has evolved from an asynchronous design to involve a blend of technology enhanced synchronous activities. To address the identified problems with feelings of loneliness, confusion and low motivation blended learning must also be designed to support collaboration, rich teacher-student and student-student interaction. The aim of this study was to explore the relationship between collaborative learning, retention rates and learning outcomes in university courses given in blended synchronous mode. The important main research questions to answer were: “What is the relationship between student satisfaction, student interaction, learning outcomes and retention rates?, and: “What kind of variables could be used to describe how group work is being conducted? The overall research strategy was a case study approach with data collected from multiple sources. Teachers from 37 courses in two bachelor programmes answered an online survey to investigate the relations between student collaboration, student interaction, pass rates and students-overall impression of courses. Survey answers were analysed and compared to answers in course evaluations and results in national study documentation system. Findings indicate that there is a correlation between students’ overall impression of a course and the pass rate, where students’ overall impressions are based on the course evaluation. There is also a correlation between students’ interactions in a course and students’ overall impression of a course, where a high degree of student interactions results in a more positive overall impression. There were no correlations regarding student grades, and the various types of group work and the design differences between the two programmes require further analyses. [ABSTRACT FROM AUTHOR]