There is currently quite a strong tide of opinion, in UK education, in favour of gender segregation for the duration of their secondary schooling. However, gender segregation is not a new phenomenon. Girls and boys usually went to single-sex schools before. Co-education came about in around the 1960s, when non-mixed education fell down. Now people are questioning if the decisions made before, on bringing together boys and girls, were actually the right ones.

The basic question is does one system (segregation) or the other (non segregation) offer significance advantages in terms of, i.e. academic achievement?
For those who are in favour of gender segregation, they claim (from studies conducted in British Schools) that each sex matures (socially, intellectually and emotionally) at different rates - girls usually mature before boys. Members of the two sexes also have very different natures; for example, boys are usually competitive, whereas girls are usually collaborative. There are certain subjects at school which people will usually classify as one-sex subject (gender-stereotyping of others). For example, science would be classified as a male subject and language(s) as a female subject. This idea discourages one sex or the other from joining in as much, in a co-educational place (therefore, marks might be reduced). Being surrounded by boys or girls (those with mutual sexual awareness) in adolescence can often be a significant distraction from work, lowering the marks of some. These points are very important in considering segregation. Those in favour feel that in a co-educational environment it is more likely that marks will be reduced (distractions). The studies in British schools show that pupils perform academically better apart (possibly one of the strongest arguments for segregation).
All these explanations are very good and true, but segregation may still not be the best system.
There are those who find that co-education is better than segregation. Single sex education is not necessarily beneficial and does not necessarily mean that there will be better achievement in school or better performance. Although the genders might mature at different rates, they can still help each other. Each sex can help the other along; can inspire. As I said before, it’s usually girls who mature quicker than boys, but this can be a good thing for co-education. Also, the natures of the two sexes can be influential on each other; with each sex preferring a certain subject and males being more competitive (helps each other to want to do better at what they are least good at). In a co-educational environment, this competiveness and subjects could not only discourage but encourage people to be better. A very good argument for not separating the sexes might be, perhaps, that splitting them gives the perception that boys and girls are completely different; that they can’t try for the same jobs or that they work better mixing and socializing (in their adolescence) with the same sex. In the century we live in, boys and girls ought to be able to aim, i.e. for the same kind of jobs. Segregation could hinder relationships for the future. If one is working in a single sex environment, they are likely to be shyer when approaching the opposite sex. One might gain more confidence if they are mixing with the opposite sex, rather than with just their own sex.
In conclusion, I feel that non segregation is the better system.

Please read through and comment. It is not finished. It must be structured and reasoned. I'm not to confident so please help...

Your basic ideas are excellent.

However, I suggest you let your essay sit for a day or two, and then go back to it to do a thorough job of editing.

For instance, in your first three sentences, I'm sure you'll be able to improve these sentences:

"There is currently quite a strong tide of opinion, in UK education, in favour of gender segregation for the duration of their secondary schooling. However, gender segregation is not a new phenomenon. Girls and boys usually went to single-sex schools before."

In the first sentence, you should change "their" to "the students" because it's unclear to whom "their" refers. In the third sentence, you should clarify what you mean by "before."

Please edit your paper and repost it. We'll be glad to help you after you've made an effort to improve it.

By the way -- I was married to a writer for 25 years and typed his manuscripts. Professional authors are rigorous about self-editing before they submit their works to professional editors.