If we sound like a broken record when it comes to BJUP curriculum, there's a reason. None of their curriculum were originally designed for homeschoolers. All Bob Jones courses were originally intended for classroom use in Christian schools; homeschoolers must adapt them for home use. The approach taken, therefore, is that the teacher will provide active instruction in the form of lectures and discussion, and not that the student will be largely responsible for teaching himself. The junior high and high school BJUP science textbooks are no exception. Information is presented primarily to teachers so they can in turn present it to students.
At the core of each year's course are the complementary student and teacher texts. All teacher editions are spiralbound in two volumes. Student texts are one-volume. A separate student activity manual is available for each grade with solutions for these activities in a separate teacher's edition. For each grade there is a test book and test answer key, as well as a variety of lab materials for experiments and hands-on learning. Because of the amount of materials required it might be easy to think this is a text-driven course, but it is not; it is instruction-based and requires lots of teacher involvement.
Each concept is thoroughly covered. Lesson plans in the teacher's edition provide everything the teacher needs to present the material, even if the teacher who doesn't have much personal background in science. All the materials fit together to provide a unified whole.
This is quite possibly the best science curriculum for older students we carry, but only if you're ready and willing to spend a lot of time personally instructing your students. While some parents prefer this approach, others simply can't afford the time for a single subject, and there really are no shortcuts in the system of BJU science.
BJUP has been at the business of making curriculum for a long time, and they understand what works and what doesn't. Unfortunately, they don't generally have homeschoolers (and many of the specific issues homeschoolers face) in mind with their courses. A parent teaching more than one child all subjects at different levels just isn't going to have the time required to teach most Bob Jones subjects. However, if you want to focus on a particular subject and are willing to really delve into it, BJUP might be the best way to go. This really is a good program, just not particularly homeschool-friendly.