There is some debate over whether or not students should be divided based on their intellectual abilities. In my opinion, it is a good idea to put students in different classes according to their talents, but I do not deny the benefits of mixed groups.
One of the primary arguments for separate classes is that individuals get ahead only when they are dealing with something challenging, which opens for them new horizons. However, curriculums are designed for average students, thus limiting gifted ones. As a result, extrodinary kids have to waste their talents on topics that are too primitive for them and do not allow them to develop their innate abilities completely.
Another point to consider is that there is nothing more encouraging than the presence of a brilliant personality. In other words, people start working harder and using more of their inner potential, when they want to keep up with someone. Such a stimulus brings them to a new level. Take, for example, a person with good but not remarkable abilities; a lack of competition might make them think too highly of themselves and ignore the necessity of extra training.
Finally, I think that despite mixed learning, kids and their self-esteem benefit more from a more individual approach. Undoubtedly, no matter how talented a person is, seeing someone more extrodiary by nature cannot but affect self-confidence. It may lead to depression and deprive them of enthusiasm. That is why it is important to take into account the level of natural aptitudes before forming classes.
In conclusion, a child can take advantage of both kinds of classes, but those of separate ones outweigh, as give them a chance to develop in a more suitable environment.