Part 3: Please read parts 1 and 2 first.

Learning at home is positive for disabled children or for those who live far from the school (in a mountain village or in a country area). Nevertheless this,there are serious downsides:; maybe parents know very well only one or two subjects;. Moreover parents should judge their sons when these do a text: it isn’t educational.

1/ "Nevertheless" stands alone; it doesn't need "this". A similar expression is "regardless of this" but "nevertheless" is more concise.
2/ Colons are used in front of a list of items, usually in list form. If you're simply breaking up a sentence into two thoughts then you would use a semi-colon. However you should only use one per sentence. This would be better broken up into individual sentences.

3/ The first downside is not completely wrong but does not sound natural. A native speaker would say: "Maybe parents know only one or two subjects very well.".

5/ You wouldn't usually use "these" to refer to people (except in the sense of "these people over here"); normally it would be "they" or "them".

In my opinion learning teaching (or educating) a child doesn’t mean filling him with notions but learning values such as rispect respect,solidarity and honesty. So I think that it is fundamental essential to send children to school.

1/ "Learning" is what the student does, "teaching" is what the teacher does. It's the difference between imparare e insegnare.

2/ When you are in the process of doing something (like teaching or learning) you would normally use the gerund form; "filling" rather than "fill", learning rather than learn, etc.

3/ I know why you used "fundamental"; you would be coming from "fondamentale". However the meaning of the two words is subtly different. Not by much, but enough to make that sentence just slightly off key. "essential to" is closer to what fondamentale would mean.

This is part 1 of the corrections.

Wow... I can guess why you haven't received any corrections yet. One big suggestion; please do not write in ALL CAPITALS. It is regarded as being the equivalent of shouting and more importantly it is really, really hard to read for long. I'm going to convert the text below.

Teaching Children At Home

1/ In English, you usually capitalise the first letters of every word in a title. 2/ Using the Gerund form (teaching rather than teach) is usually preferred for titles like this.

Sometimes parents are the teachers of their sons children, more often children go to school.

1/ "Sometime" is "at an an unspecified time". "Sometimes" is "occasionally", which is what you need here.

2/ There is a difference between English and Italian here. In Italian "figli" can mean either just sons, or a mixture of sons and daughters. The same is not true in English. In English "sons" are males only. You would therefore use "children" where there may be a mixture.

Yes, believe it or not Italki claims that this is over 5000 characters because its method of counting formatting is feral. To be continued...

Part 2; please read part 1 first.

Learning at school is good because students can make friends and can learn how to cooperate in group,an ability that will be useful in the world of work too.

1/ In this sense you would always use "how to" rather than just "how". "How" is an adverb. The verb would be "to cooperate". The Italian equivalent would be "come cooperare".

Children can share informations and points of view in class.

Information is always singular in English; it's a collective noun. In this case though "knowledge" may be a better word since what is shared is often broader than just facts and figures.