What exactly are they struggling with? If you're unsure, ask them whether it's that they don't know
what to write, or they don't know
how to write it.
If it's something like run-on sentences, then maybe impose a general rule for now, like no sentence can be over 3/4 lines long (depending on handwriting)
Another one I've found good is to prevent fragmented sentences, tell them not to begin a sentence with a verb. Esp. in L.A. I find the tendency is to continue ideas between separate sentences like: "The author uses__ to make us feel __. Suggesting that we should reconsider our views about__." Changing it to 'This suggests' is an instant fix, pretty much.
If it's really clunky, you might have to revisit some basic grammar rules. Don't make this too remedial, as it can hurt their self-esteem a bit, but explaining different sentence types or word forms will make a lot of difference in the long run.
Or if it's just general expression, it might be a vocab issue. Not having the language to deal with concepts can make it really difficult for students. I don't know much about global politics but I'm assuming there's quite a bit of coursework to cover, you know, globally. So perhaps it's actually a problem with the content, and your students just don't know how to approach a question?
When it comes to correcting their work, divide it equally (If they're up to it.) You correct every few sentences, but leave a few for your student (up to you whether you underline these or just leave it for them to find.) See if they can a) determine what's wrong and b) work out how to fix it. This should help work out what the problem is; if they don't notice there's a problem and the sentence makes complete sense to them, you'll need to explain the grammar, but if it's just a matter of fixing what they know sounds iffy, then that should be easier.
