It is a VERY good idea to take a course like this before law school. I can also suggest Wentworth Miller's LEEWS program, which I took during first year and found very helpful, and the Planet Law School DVDs, which are not a course but still informative. You should also read as many books about law school as you can before starting. Finally, there are a number of prelaw tutors out there who work with students to get them ready for one-L year.
The goal of these efforts should be to know exactly what to expect before you set foot in the door. Many of the top students in my class weren't smarter than anyone else -- they simply came to law school knowing exactly what to do. Feel free to e-mail me if you have any more questions.