The activity "Mathematics classes" I started on June 2016. It is involved in the component SERVICE in CAS. I help my good friend in maths. He is of my age, so we are learning similar things during Mathematics lessons at school. However, he has some difficulties related to Mathematics, so I suggested him that I can help. We meet with each other and solve exercises related to certain chapters, but also we solve tasks from previous years secondary school-leaving examinations. It is good CAS experience, because I can share my knowledge with somebody else and I also improve my mathematical skills, because I solidify concepts that I should remember, I solve more and more exercises, so I am able to do it more quickly now. The biggest difficulty that I faced doing this activity was the fact that I had to learn how to explain some things in the possibly easiest way. However, my friend tells that he is glad to be taught by me so I think that my methods are quite  successful :)