My son and I went through most of the Starting Points (Cornerstone Curriculum) book last year. As I've told Joanna, we stretched it out to THREE semesters (and we're still going to go through a couple of the books this semester). I recommend it to anyone who wants to discuss the various worldviews with their Jr. High or High School students, whether they are homeschooled or not. I counted high school credit for three semesters.
I used to like to do Summer projects with my daughter, even though she went to public schools. She would have loved this. For Summer use, you could just purchase the syllabus and then order the materials separately which you'd like to study. I think it has a little bit for everyone, obviously it is good for people who love books but there's a section where you can watch various films and discuss the worldview of each film.
However, for the class I'm teaching, there isn't time to go through this book. For the first third of the class, I had them going through newspaper articles and looking at them from a worldview perspective. Then we spent a couple of months reading through A Christmas Carol, enjoying that book and seeing how Dickens's "view of the world" influenced his writing. Now we are looking a little more at the concept of what a worldview is and how a Christian worldview is different than that of a person who does not have a Biblical worldview.
Here are the three articles I printed out for my students by doing a cut and paste to Word (giving full credit at the bottom of each printout). The first one we actually discussed in class (excellent information!) and then the second two were given to review at home.
Christian Apologetics and Research Ministry
If you want a great book on the subject, I can't say enough good things about Nancy Pearcey's book called Total Truth. Wonderful book, she studied with Francis Schaeffer (whom I adore). However, this book takes his teachings, her further education, good writing, and makes it understandable. (If you've ever read Francis Schaeffer's books, you will understand what I'm saying!)