One of the most egregious failings of the government schooling system (and probably a lot of non-government schools) is that students are not taught how to write, as this fine USA Today articlemakes clear. Instead of graduating from high school with reasonably good writing skills, most students now graduate from college with weak ones.
The article doesn’t really go into explanations, but I think there are several.
For one thing, grading writing is difficult. To take a red pen (or any other color, now that red has been called a threat to the self-esteem of students) is hard and usually thankless work. Students grumble and whine about pickiness. It’s much easier just to give multiple choice questions on a test that can be run through a scanner so you have your grades in a few minutes. Rarely are teachers required to given written assignments and carefully grade them, so most of them don’t.
Second, a large number of teachers are products of the system and are not good writers themselves. (Sometimes they unwittingly reveal that fact when they go on strike and wave homemade picket signs reading something like, “Schol unfare to teacher’s.”
And third, one of the tenets of “progressive” education theory is that students must be allowed to develop their “authentic voices.” That is to say, it’s bad for teachers to correct poor writing since students must be allowed to freely express themselves. A wonderful, Rousseauian rationale for laziness!