Many homeschooling parents become intimidated when it comes to teaching upper level science courses. I have used several different highschool science programs and both my children and I have found Apologia, by Dr. James Wile, to be excellent.
The Apologia science line has grown over the last several years to include:
General Science (7th grade)
Physical Science (8th grade)
Biology (9th grade)
Chemistry (10th grade)
Physics (11th grade)
Advanced courses:
The Human Body (advanced biology)
Marine Biology (written by Sherri Seligson in the Apologia format)
Advanced Chemistry
Advanced Physics
My children and I have personally used Physical Science, Biology and The Human Body, advanced biology. The books are decidedly Christian, very interesting and well-written in a conversational tone.
Experiments are presented throughout the book to help reinforce understanding of the concepts taught. The general and physical science courses include experiments that are done with easy-to-find materials, though it is a good idea to check and make sure that you have all needed items ahead of time, so you won’t be running to the store for a missing item.
The biology course is written so that it is easy to skip the experiments requiring a microscope if you cannot afford one, as there are plenty of experiments that don’t require a microscope.
I highly recommend getting all of the suggested experiment supplies for the advanced courses, as they become a more integral part of the course. My 11th grade daughter thoroughly enjoyed going through her advanced biology course. She typed her own blood, dissected a cow heart and a fetal pig!
Last, but certainly not least, Apologia Educational Ministries offers ongoing support. They have a contact number and contact e-mail address at the front of the book. My children found the concepts in the book well-explained and never did contact Apologia, but the offered curriculum support could become important with more math-heavy science subjects, such as chemistry and physics.