Some years back, Idaho imposed a senior project requirement on all the high schools in the state, at least partly to make sure that graduating seniors could actually write. I think it works. In 2003, I was utterly floored at how few of the upper division history majors in my Constitutional History class could actually write at college level. I had a student turn in a paper where 1/3 of the sentences--were not. I had students tell me that this was only the second research paper that they had ever written--and did it show. I would say that only five of the twenty-five research papers that I received that semester were what I would expect of upper division college students.
By comparison, these essays from the freshmen in my U. S. History class at College of Western Idaho (a community college) are gratifying. They aren't perfect, of course. But so far, of the ones that I have graded, many are good and several are actually quite good. Most students at least know how to write competent sentences; some students are combining competent sentences into well-structured essays. A few students have not achieved sentence structure competency (or competency in capitalization, or punctuation), but nonetheless, have well-structured essays.
There is room for improvement for all of them, so far. Still, many of them are starting with what would have been considered high school level writing skills when I graduated from Santa Monica High in 1974.