In conclusion, it should be emphasized that materials developers, who are in most cases also teachers, should reflect not only methodological principles and approaches, but consider that materials need to be written in such a way that the teacher can make use of them as a resource and not have to follow them as a script . If such a material is developed, then both teaching and learning is a challenge. Moreover, such written educational materials might increase student’s interest in studies, respectively his/her motivation for self-study