I asked a similar question a few weeks ago. I did not require an accredited option though. Our school told me that she could do anything to get the content and they will just have her take the end-of-the-year algebra test that she would be taking if she were in the class. That is enough for our district to prove she knows the content.
The responses I got on this forum were great. The one I most remember was purely online though (that's the one we are choosing) - it's called ALEKS. I also heavily considered EPGY, but it was quite expensive. You may want to search algebra to see what else people suggested. Good luck!
