Neither of my children were very excited about science as they are more artsy people, so we did not go out of our way to do AP courses or take SATII's which science minded kids will want to look into.
My daughter Used Hippocampus for Environmental science. She used it in conjunction to one of the recommended textbooks on the site, and mostly followed the hippocampus format. I just mapped
out the lessons so she could pace herself. This was a very enjoyable course thanks to the instructional videos and well paces assignments.
My son did physical science in middle school, but if I remember correctly, we counted it as a high school course. The colleges has no problem with this. He actually took physical science in a classroom environment and while he came out with full knowledge of the table of elements, he felt that he didn't learn a lot. Once a week was not enough for science, which is why he did most of his academics at home after that.
My daughter is doing physical science right now as a high school senior. She is using a classic homeschool program, Alpha-Omega life pacs. Alpha-Omega doesn't exactly have a physical science course, per-se, but what we did was pull out 800 and 900 level Lifepacs to pull our the physical science related subjects. In all, we have 8 Lifepacs for physical science. I probably could have found a more rigorous course, but physical science was an afterthought. As far as the colleges were concerned, three science credits were plenty. It was the accreditation agency that required 4, so we had to squeeze it in and were therefore happy with a basic course.
Another option for physical Science, might be the Glencoe text book (used for very little) with the online resource.
Both kids used Hippocampus for biology, along with the one of the recommended textbooks, Inquiry Into Life. They did this course together, my son was grade 11 and and my daughter was grade 10, so it just made sense. My kids did start with the AP course and moved to the General Biology course when they realized that there was too much detail to learn in an hour or so a day. For labs, we did what we could in the house, but that was not much. They did a lot of virtual experiments and explored a lot of sites that specialize in virtual dissections.
My daughter used an online college course for Chemistry. It was through MIT Open Course program and it is called Kitchen Chemistry. All of the experiments were done with ingredients found in the pantry, but I did have to order a few non-kitchen essentials like Pectin, dry ice, and a few chemicals used to bake in bulk. It was quite a tasty course, as we ended up eating her experiments every Wednesday, the day she chose to do them. She loved the textbook so much, I have never seen it again, and gather I won't get it back to sell it. Her accreditation agency approved it as an acceptable Chemistry course. The course was free, and the textbook On Food and Cooking - Revised Edition (Google Affiliate Ad) was probably $20.00 and the weekly grocery/experiment list was about $15.00. She managed to learn the Element tables in the course of this class, so I was pretty happy with it.
Intro to/ Physics:
My son did part 1 of this course with the online public school at home program. He was so frustrated with the teacher and software program, that we switched back to Hippocampus for part 2 of this course. Hippocampus has a couple of different levels for physics even AP levels, so you can choose to do math-heavy physics to math-lite physics. I feel like Hippocampus is the best option for this course.
Other: If your student has earned any boy scout/other scout badges that pertain to science, you can award them credit for their work.
Science summer camps can be great for a 1/2 credit in science.
In summation, for kids like my own, who were not excited about science, a site like Hippocampus can give them most of the science they need. Except for Chemistry, which I feel like is only for further explanation, not the core of the subject. Had my kids been more excited about science, I would have taken them to lab classes which are readily available in our community in addition to the Hippocampus classes. Learner.org, also has science videos, which I think are great, but my kids were completely non-plussed. They felt the videos were too old fashioned. (insert rolled eyes here.) Aleks.com which I also found too late has a nice AP chemistry program.
Also important to young scientists are science museums, science camps, and science workshops. There is one such workshop that travels around the country, which I strongly recommend folks check out. It is done by Landry Academy. They also have online classes for science enthusiasts.
Other subjects covered: (linked as I complete them)
Foreign Language &The Arts