Some parents are intimidated by the idea of homeschooling through high school, but it really isn’t that much different from the younger grades. I have graduated two children from 12th grade so far, and they have had no trouble getting into and succeeding in college. From my point of view the one big difference between high school and younger grades is that in high school you have to keep good records of schoolwork.
High School record keeping for homeschoolers is important, because as a homeschooling parent you are also serving as an administrator and guidance counselor. At the end of high school will need to produce information for transcripts and college applications, and good high school record keeping will make that whole process much easier.