Finally, you can use your journals as a sort of treasure trove from which you can pick out ideas for research papers and term papers, even essays. You'll be amazed what you've written down over the course of the semester when you flip back through the pages in search of topics for papers. So, you can choose one (or four) and write as many papers as you need, and this way, you know your topics are ones you like.
One assignment type I find particularly useful is the journal entry (sometimes called a reflection). These are just what it seems, almost diary entries, based upon a particular class reading, class discussion, or other issue which the professor has deemed important enough to think about. Usually not graded as to grammar, punctuation, or other similar parameters, the journal entry is the ideal place for a student to reflect upon concepts, ideas, thoughts, without worrying about the writing itself.