Here is an interview with Nan Miller about her recent paper on the problems with college writing courses. (The whole paper is available here.)
One of the questions asked about students who come into college and struggle with writing even a single paragraph because they have gone through their K-12 years without having to write much, the easily scored True/False or multiple choice question (often taken from a test bank supplied by the company that publishes the textbook in use) having supplanted essay questions and papers to a great extent. Back in my own teaching days, I often ran into that. After doing poorly on essay questions, students would complain that all their tests in high school were True/False or multiple choice. Those students usually had writing abilities that wouldn’t have been good enough to get you out of fourth grade back in the old days.
Many students come into college after 12 years of schooling when no one was paying much attention to their ability to form sentences. If students aren’t even learning how to use the English language, isn’t K-12 mostly a waste of time?