Here are the options I located for secular high school science which I was interested in using:
1. Science for High School a rigorous program that supplies lab kit materials and is based on an unusual approach – each week, students are given key questions to research and answer. What you use for the research is up to your family: websites, library materials, textbooks, etc. The parent’s guide has an overview of the bare minimum your child should orally explain to you at the end of the research. Then the student completes a lab assignment which explores key components of the theme.
2. Oak Meadow – a homeschooling company of long standing. Students are provided with a course guide, a main stream textbook, a kit for lab materials and a teaching guide for the parents (available separately, phone to ask for it). Students are told which pages to read and are given questions to answer at the end. Option to pursue the course as a correspondence course is available.
3. Nebraska University Independent High School program. Similar to the Oak Meadow approach but only as correspondence course. (I believe. I’ll be frank: things are starting to run together and I stopped researching this one earlier in my process of elimination.)
4. Choosing either the Holt textbook or the Glencoe textbook (or textbook of your choice) and inventing your own course of study using the assignments, review questions, and quizzes in the text. Source lab materials independently. Not surprisingly, there are oodles of catalogues.
5. Your local provincial distance education courses. However, having just used one, I would rather have used one of the full-color textbooks on which it was clearly based. The editing on this was poor, the presentation sloppy and erratic. Your province might supply better materials than Manitoba, but the problem is that even a careful review of samples won’t turn this up. Only by dealing with it day by day do you see the presentation’s strengths and limitations. Homschooling’s great weakness is that you can’t really learn from experience and teach the course better next year. Like a famous fish, we have to ‘just keep swimming, just keep swimming’.
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Those were the strong favourites to start. By the end, only Oak Meadow and Science for High School were vying for our money. In the final analysis, we went with Oak Meadow because our family’s struggle with vision problems means that researching topics every week would be wearying and possibly demoralizing. I really want Gr 10 to leave Sandra feeling smart and full of skills. Our top focus for the year is confidence in writing. Science needed to be a little simpler for us.
Handmade Homeschool 
Too late now, but maybe this will appeal for another year or someone else:
http://www.secondaryscienceeducation.com/index.html
I hope that Oak Meadow proves to be a good choice for your family – it sounds like you put a lot of thought into it. I will be curious to read about how it goes – as I said in my recommendation I’ve only gone as far as 8th grade with OM, but like it very much. Hope you have a great (scientific) year!
Thank you for sharing this. My dd will be in 7th grade and I’m already finding it difficult to find a good secular science program to use. I’ve bookmarked these to consider in the near future!
We tried a provincial science course last year (in Ontario) and overall the biggest issue was a lot of time and effort for not a lot of learning. It kind of took over the first semester. I have to admit that I’m not a very hands-on parent but we’re not doing that again.