If a pupil falls seriously ill, it is not only a shock for the pupil himself or herself, but also for his or her family and classmates. The project “Virtual Classroom” of the Heilbronn University in cooperation with the foundation “Big Help for Little Heroes” therefore tries to maintain the daily school routine and thus the contact with friends as far as possible with the help of mobile telepresence robots in the classroom from home or from the hospital. Here there are both technical and human factors that contribute to success or failure. Based on a systematic literature research and practical experience, these factors are identified, discussed and weighted in this paper. If the mobile telepresence robot is used successfully, this pays off twice for the pupils affected: It has been shown that pupils can progress socially as well as in school, even if attendance at school is not possible for a long time.