It is sometimes argued whether individual classes or group lessons are more beneficial in studying process. I personally believe that learning in groups is more effective.
On the one hand, one-on-one lessons can be good because of some reasons. Firstly, teachers can see mistakes of their students better when they work individually, which ensures students a good understanding of mistakes made and provides an opportunity to work on each of them. Furthermore, learners can ask questions whenever they want or require the teacher to explain the topic once more if they did not understand it, which is nearly impossible while studying in big groups.
On the other hand, learning in group lessons is advantageous because of several reasons. Firstly, it is cheaper than studying in individual classes, therefore lots of people can afford the price of them. Another reason why group lessons are better is the motivation which students can get from competitions during studies. Some students can learn better or push themselves to work on themselves harder when they are competing with their peers. For instance, some students does not want to search additional materials to improve their understanding of the lessons because they think what their teachers give is enough, whereas working in a group encourages students to learn more at least to keep up with other groupmates.
In conclusion, group lessons are more effective because of the reasons mentioned above.