In this research my main purpose was to find out if the use of flipped classroom as a teaching method would improve the learning effects in mathematics. One of the main challenges for teachers today is the lack of time to help each student. Would this improve by using flipped classroom? Flipped classroom means that the pupils learn the new theory home by watching a video and that they work with the tasks at school. This means that all the time you spend earlier at school working with the theory, now are available to spend on helping each student. In the study I have used different methods to find answers to my questions. I have observed the class while they were working. I have made interviews and at the end of the study I made a survey for the whole class. The information I got from the pupils, were used to improve and change my strategies in the research. The research was made in a small class and because of this I think it is difficult to say how precise the findings in my research are. One thing I can confirm though, is that by flipping the classroom gives the teacher a lot of opportunities to vary the teaching at school. The pupils gave also feedback on the opportunity to see the video several times and also to use it in preparation before tests was a huge positive thing about flipped classroom. I cannot say how much flipped classroom improves the learning of mathematics but the feedback from the students was clear. They would continue this way of studying if they could choose.