As a grad-student I really appreciate this question. As a Humanities student most of our writing is text. I found even at under-graduate level a substantial amount of time could be taken up going over the same writing issues (usually after assignment hand-backs) over a number of course modules. It amazed me that there was not a module to at least give the basics in academic writing.
I have noticed though in Ireland(my home country) that there is a number of Academic Writing Centres starting to set up in Universities. At the moment they are voluntarily drop in centres where you can get advice on your writing.
In the case of the university I attend
The AWC offers free one-on-one tutorials on essay writing for NUIG students. Last year, AWC tutors helped over 500 students to overcome recurrent problems with grammar, punctuation, spelling, and essay structure.
They also run group workshops at certain times of the year for different levels within the University, so some are aimed at under-graduate and some at post-graduate. Normally at these workshops you bring some of your writing and as a group you give each other advice on improving our writing style.
Finally they run an online course which works in the following way.
Online students are assigned weekly writing tasks and editing tasks. Editing tasks consist of specific questions which assist students in providing constructive feedback rather than criticism. Guided editing tasks help students to re-evaluate and improve their own writing. Students then rate the usefulness of the critique they received. In this way, points are awarded for effort rather than existing ability or experience. The entire process is strictly anonymous. The AWC takes on a supportive role for the duration of the course. Students receive weekly readings and emails.
A number of other universities also have a academic writing centre in place. See here and here
While this is by no means a perfect model because it requires the student to want to participate it is a step in the right direction for improving a persons writing skills.