Hey girl!
You will LOVE this! But! I began planning for the long-haul from the very beginning! 
Better explain huh? Well, as I would plan any study, there were obvious things that were fantastic that were just a bit too much for my little ones, so I planned to study those in High School before they graduated. By the time that we were edging closer to high school, I already had a full course in mind. It helped sooo much to include all of the details without getting side-tracked in the midst of high school. Make sense?
It helps more than anything to be as clear as possible about your plan before you hit those high school years. Really seek God and His plan for your children. Sounds like He is already giving you a vision of where they will be going. He has been SOooo good to do that for us too. Of course, there have also been some areas that He has sprung on us in the middle of the journey--I think that was because it was time to look in those directions--college at home/accelerated distance learning--if He had shown us those details too early I would have been too scared!
There are some incredible resources out there that can help you to hear God as you make your plans for high school. They will also help to settle your anxiety. My favorite, all time, high school author is Barb Shelton. Even this year, when we were first blessed to minister together at a convention (we usually travel very parallel paths, but rarely together!), she blessed me in our personal conversations to give me a glimpse at the incredible vision of what is JUST ahead of us. Our philosophy of education is very parallel. Sooo, if you want to homeschool the easy way into High School, you will love her work! Now, for reading tons of her work, check out her website at http://www.homeschooloasis.com and devour her articles! You are sure to come away with a great vision for what High School should be like for your children. 
Her high school book is still one of my favorites!
I am TOTALLY honored that you all recommended my book! I do have a whole series of articles coming out on "Wrapping It All Up" and "Homeschooling through High School" in the very near future. I am setting aside a whole special themed issue of HOMESCHOOLING THE EASY WAY just for this topic. These will be posted here for you guys too! In fact, you all can help me with making sure that I include everything that you need to know. Just make me a list and let me know what you need to know for homeschooling high school. I will do my best to help!
Well, must get running!
Love ya!
Cindy
