## 4 Discussion
### Summary  
The evaluation study with 46 undergraduate students examined the quality of the social learning experience in groups and the quality of the interaction experience with the NAO robot. Furthermore, differences in the quality of learning and interaction experience were explored by comparing results for students with and without prior experience in interacting with the NAO robot. The results showed that students experienced the RSCL activity of planning poker in a positive way, both on the affective and cognitive level. First, the analysis revealed that all participants, independent of their previous experience with the robot, enjoyed the robot-supported collaborative learning experience. Second, although there were only two statistically significant differences among students with and without prior experience with NAO, i.e., students without experience with NAO (n 27) felt more confident in agile estimation, while students with NAO experience (n 19) felt more bored during the interaction with NAO, there were some further interesting, but not significant, differences in the mean values of different variables. Some of these differences were related to higher mean values among students without prior experience with the robot for the variables related to affective aspects such as \"exciting\", which may be contributed to the novelty effect of a first-time interaction with a new technology. Third, the group of students with prior NAO experience showed higher mean values related to cognitive outcomes such as\"increased my knowledge\", \"stimulated my curiosity\", and \"was helpful to understand planning poker\". Although these differences were not statistically significant, they indicated directions for further research, possibly in longitudinal studies and with larger samples. It could be hypothesised that once the novelty experience related to the application of robots as a new technology fades away over time, the attention of learners can shift from the technology to the actual process and content of collaborative learning. Previous studies have already addressed possible benefits from the familiarisation effect and provided empirical evidence for the decrease in novelty experience due to the increase in the familiarisation effect over time [33]. Overall, from the perspective of the human facilitation of collaborative learning activities in small groups, the case study showed that a robot-supported collaborative learning activity like \"Planning poker with NAO\" offers useful support for a human teacher aiming to provide a large number of students with an engaging learning experience in small groups. Since the same standardised script can be repeatedly executed by the social robot without any fatigue or decreased focus, the potential of applying social robots can be seen in enhancing scalability, while benefiting a large number of students from the interaction experience in small groups. The application of social robots may help to exploit the potential of learning in small groups, such as increased engagement, collaboration, communication, and accountability. Furthermore, with a social robot orchestrating a collaborative learning activity, there is more time for the human facilitator to provide individualised or personalised support and feedback to the group of learners. The resulting co-facilitation approach of a robotic and human facilitator can benefit students through access to both standardised (robot) and personalised (human) support. Considering the positive results of the study presented in this paper, combined with the positive results of previous studies in similar areas, it is possible to envisage robot-supported collaborative learning (RSCL) as \"a new paradigm for higher education, in which the group facilitation can be supported by social robots\" [8]. It is important to emphasise that applying a robotic facilitator should fulfill a supportive role for the human teacher.