@mindfully - As Billy Crystal says in Throw Momma from the Train, “A writer writes.”
Sitzfleisch (not sufficient but necessary)
I think that any literate person can become a competent writer, that is, able to put understandable thoughts on paper, although not everyone can become an interesting writer. There is something to be said for talent, whatever that means.
Two books:
“The Forest for the Trees: An Editor’s Advice to Writers,” by Betsy Lerner
“Thinking Like Your Editor: How to Write Great Serious Nonfiction and Get It Published,” by Susan Rabiner
Advice: revise and revise and revise yet again. And then revise again. I had a professor in college who said the key was to write a draft, throw it away, and then wrote it again. After 10 times, you might have something decent.
koshkas,
"His mind just jumps from one thought to another and while it can be acceptable in a discussion, it absolutely doesn’t work in writing - no matter the amount of practice and advice 
We are still looking for solutions… Do you have any? "
-As I have stated before (and your S. has proven once again), I donot believe either that reading skills and writing skills are correlated. I wish, somebody could have given us solutions on how D. could have improved her reading skills (not needed any more). My personal conclusion is that it is NOT possible for somebody who does not like to read to imporve the reading skill.
By the same token, and, again, as I stated in my original post on this thread, I believe that it is possible to improve the writing skill ONLY by wiriting A LOT. And if one does not enjoy writing (just like my D. does not enjoy reading), then I do not see how it could be improved.
One exercise my D. is in habit to go thru before she writes any paper, she “writes” it in her head. She developed this habit because of her very busy life that she has chosen for herself at the young age of 5. She told me that by the time she actually is ready to type her paper, she has a clear outline, and most of paper in her head…“written” during long swim practice during time when they do not need to listen to a coach and do not talk to each other, but rather swim…and NOT focusing much on swimming actually helps it also. Later, she used to “write” her papers while walking from class to class at college, driving or any other activity. This habit also helped her to go over material in her head before any exams. I do not know if this “technique” is helpful to your son at all as everybody is different.
At contraire. Of course she still needs reading skills. Lots of journals to read and conference materials to digest to stay current on her field.
I’m not sure I agree with the blog or diary suggestions. Simply increasing the volume of your writing does nothing to improve its quality.
What kind of writing are you hoping to improve? Essay? Creative/ fictional writing? Research papers? Each has a different flow, and being good at one doesn’t always translate well to the next.
I think that, if there’s time before school ends, my first stop would be with my current English teacher. Take a look at the writing you’ve done in class this year, and pay particular attention to any comments you’ve received. Then go back and rewrite those assignments, trying hard to improve where your teacher has found weaknesses. (Yeah, school ends for us tomorrow. So the timing may be wayyy off.)
How’s your grammar? I don’t know a preposition from a participle, but I can hear bad grammar. Grammar might be a good place to start; I’m sure you can find lots of books at B&N or Amazon that will get you started.
Oh, and turn the spell check/ grammar check off when you begin to write. You need to learn to self-edit before you let a machine do it for you.
@MiamiDAP, Thank you! Those are very good ideas - I will try to pass them on (if only he would listen!).
@bjkmom - I don’t think that plain increased volume of writing is completely useless - while not as efficient, it still can make one think and analyze his own writing more. The type of writing is not as important. They need to be able to clearly state their purpose, in detail if needed, and do it creatively enough to be interesting for the reader. The grammar and spelling are usually not the problem - they can be easily checked.
And the school teachers - well, I don’t even want to get started! They contribute at least half of the problem. We now have a tutor who is trying to repair the damage done by those “teaching geniuses” but it’s hard with the genuine hate for writing honed by years of incapable teachers! At least we were able to save his love for reading.
My son is an excellent writer. His writing skills were atrocious al through high school. He started reading a lot once he entered college, and not just for his major. He probably reads 3-4 books per month on average on a variety of topics. Once he started that, his writing just took off.
^But if a person already reading A LOT, much more that 3-4 books per month and still cannot write well, than he still needs to increase the amount of books that he reads? it does not sound logical. Aside from the fact that person is enjoying the reading and should continue with his favorite activity as he is very lucky to love such a great activity as reading, aside from this fact, increasing the number of books, say from 10 to 13 (as an example) most likely will NOT improve his writing as he is already reading well beyond the average amount.
@koshkas: from what you’ve described it sounds like your son just needs a little help with the mechanics of writing: how to make transitions, tie ideas together, etc. A good way to do that–I’m assuming he’s in high school–would be to sign up for a writing course at a local community college. That should help him learn some of the mechanics he’s missing. if your son is in college, have him go to the college writing center. There are tutors there who can help him. That’s what they’re there to do.
These are all great ideas. If there are issues of organization, I would put in a plug for the now-less-popular Five Paragraph Essay. It forces a structure which, once the student masters it, (s)he can depart from comfortably. It worked for my daughter, who had a real hard time in elementary school (just writing is not enough), improved with the structure in high school, and did well with all types of writing in college.
A few posters have suggested working with a good editor who can mark up your son’s written work and identify the areas that aren’t clear or need reworking. This is a good first step, but when that editor reviews your son’s written work and breaks out his red pen, all he will be doing is showing your son what he did wrong. That’s a good first step, but it doesn’t get your son all the way home. If your son’s primary weakness is organizing his thoughts when he presents them in written form, he needs to be shown more than where his writing was weak or disorganized - he needs to be shown how his thoughts should have been organized. You may find a teacher who is willing to put this much time into assisting your son, but my guess is that you will have to find a good writing tutor (your son’s teachers may be able to recommend one). The tutor would be able to take one of your son’s written assignments and go through the normal editing process several times with your son. Once that is done and your son has improved the writing quality as much as he can, the tutor can then show your son how he/she would have written the assignment. As long as this last step comes after your son has put in the effort to improve the writing on his own it can be extremely valuable.
I don’t teach writing for a living, but I have mentored a lot of young attorneys, and this is the most effective tool I’ve found for improving legal writing. Legal writing isn’t much different from the expository writing your son will be asked to do in high school or college, so the techniques should apply equally well.
A pox on the five-paragraph essay! 
Seriously, it does teach one basic idea of structure, but knocking it out of my first year comp students is a real pain. The structure basically bypasses a complex argument in favor of a list. “I think this cuz three reasons–reason 1, reason 2, reason 3–those were my three reasons. Done.” Bleh.
But I can’t blame this on the high school teachers, since all the standardized tests want it, so that’s what they teach to.
Garland, your students future employers will thank you.
You cannot imagine how many college educated kids cannot write an “executive summary” of a lengthy research report, or do a summation of a complicated project analysis with any sort of structure (oh how I love the five paragraph essay!)
I’ve seen new employees basically write a laundry list- first this happened. Then we discovered something else interesting. But wait- then we got new information. What are the conclusions? I have no idea but I want to describe to you something fascinating that I read on page 28.
By the time you are working it’s too late. We have communications training programs designed to take good writers and make them great. We can’t teach basic Freshman composition! And we have no interest in hiring someone- even entry level- who can’t write a coherent five paragraph summary which includes three main ideas, a hypothesis, and something approaching a synthesis or conclusion. If I have to wade through a 12 page “blah blah blah” for everyone who works for me- frankly, I’d rather read the primary sources myself and draw my own conclusions!!! It’s faster.
You are doing god’s work teaching the five paragraph essay!!!
My son took an online course from CTY called “Crafting the Essay” that was helpful in improving the technical aspects of his writing.
Strunk and White.
A tutor (my daughter is currently volunteering as a tutor in a city high school volunteer program, and her main student has gone from C and D grades to B, maybe even a B+ (waiting for final paper grade!). This was mainly by working on organization, sticking to an outline. And learning how to research, absorb and articulate clearly. A good tutor should not be too directive, can ask questions, help with structure, but needs to be careful not to do too much for the student.
My youngest is not a reader. I swear that the much maligned Facebook has been a huge help to her writing skills, as have some online college classes that require written discussion. Who would have thought…
Learn journalism.