I think the first place I would start is to look at all of the high school guides and determine which courses you need and want most and that will lead you on to how you structure 9th-12th grade. My son will be in the same boat as this. So I have poured over the guides and recorded a few alternatives on my own. You will still probably need to purchase all 4 high school guide books because you working out two different guides most years. Here are a few of my thoughts and then I can share my very tentative plan.
Science - The two sciences you will probably want to use as is are the Biology in WH and the Astrology/Geology science from the US2 guide. The choices you will need to make is whether or not to do the Advanced Physical Science in RevtoRev causing you to skip the science in WG (or skip the science in RevtoRev and do the science from WG). Or you can modify MtMM to make the science Chemistry worthy and skip the chemistry science in US1. In the attached link, Carrie describes how to modify the science in MtMM to make it high school chemistry worthy:
viewtopic.php?f=6&t=10600 . So it up to you which resource you decide to skip but by choosing to modify either physical science or chemistry, you can still have physical science, biology, chemistry and astrology/geology for their 4 years of high school.
Spanish - you can start this in MtMM and complete for 4 years. This will give you your high school foreign language credit.
Literature and Writing - you can use DITHOR with harder books and complete all 9 genres in a year and then complete WWTB2 for writing in MtMM for your literature and writing requirement or you could use the lit and writing from WG and then every year thereafter move the next literature/writing level.
Grammar & Math - you already probably have scheduled these at your child's level. My son is very advanced in math so he is a bit ahead but I am having him do a lower level of grammar. I like teaching him and his sister at the same time. They have an excellent learning dynamic and feed off of each other really well. With the schedule he is on, he will skip the second half of the R&S 8 book. I am okay with that.
There are some electives that I need to use from the final guide for my state requirements. I need for them to take economics, personal finance, and (I think) speech to graduate. Since those are in the final guide, I needed to include them their high school courses. I also am combining my two younger kids and really like having them do as much together as possible. Here are my plans for how I plan to accomplish this task:
RevtoRev (8th grade) - my son (and dd since they are doing the guide together and I want to teach the same thing where possible) will complete either The Exciting World of Creative Writing or WWTB2 since I plan to use with writing from WG for my son's 9th grade year. Because I had my son repeated the history and most of the guide from Bigger to combine him and his younger sister last year, I had him do the science from Preparing last year on his own. This year, he is doing the Preparing guide but I am letting him do the intermediate EE science with his older sister to give him something new to learn. When he gets to RevtoRev, I plan to use the science from MtMM this year and also have him complete the inventory study since he isn't doing that this year.
MtMM - (9th grade) - my son will do DITHOR this year and complete the writing from WG. He will complete the extensions this year. And he will complete Logic and the physical science from the WG guide. We do Latin so I am not going to add in Spanish this year.
WG - (10th grade) - my son is going to complete the speech course from US2 this year because his older sister is going to be using the US2 guide at the same time. Is this is the smartest choice, who knows LOL. My son isn't the best writer by any means but at the same time, I may settle for good enough. I am required to do speech and in the public schools, they do this in 10th or 11th grade. Since he is in 10th grade, I feel okay with this choice. Plus, I like the thought of him completing it with his older sister. He will also do the science from US2 this year because again, his older sister is doing that science as well. As for the grammar, I will probably not adjust that schedule. I plan that my son will just skip the final portion of R&S8. I could have him on track to complete it if I wanted to but I am not worried about it and I am okay if he skips that final portion. So he will do the first 1/2 of 7 when he does WG and he will have completed R&S 6 when he does MtMM. Hope that all makes sense. Finally, I plan to have my son complete Economics this year since he was introduced to econ in MtMM and he has the open space where logic was scheduled but he took that last year. That course does look challenging but my son is VERY logical. I think that if I help him, he will do very well in it. As for language, I may start Spanish or I may let him chose his own language. It is too early for me to plan it specifically but this is my plan for language.
WH - (11th grade) - The only change I am making this year is that my son hates art so I am going to allow him to take either the drawing portion of art or art history. If he decides he wants to do both, that is fine also. But I would expect he will only want to take half and that is good because I plan to add in the personal finance portion this year. In addition, my state does require a full credit of art to graduate. Since he did the nature study in MtMM and that includes quite a bit of drawing, I may include that time towards his fine arts credit. In addition, we attend a co-op and they offer art so he could easily take an art class there and that would bump him up to a full credit by the time he graduates. And for the fine art credit, it can start as early as 7th grade. My kids are in their 4th year of piano. Depending on the level they play at, I could also use that as part of their fine art credit. I feel like I have a lot of flexibility here and so I am only going to push for him to do 1/2 credit unless he feels passionately that he wants to do the whole thing.
US1 - (12th grade) - I don't plan to take anything out or modify anything but I intend for my son read the book, "I don't have enough faith to be an atheist." It may be something I have him read over the summer between 11th and 12th grade. I may or may not have him complete the student workbook. It looks like a great book. I might even just have him read it the year he does WG so he can at least discuss it with his older sister even if he doesn't complete any of the written work. I don't know how and when I plan to use it but I am leaning on doing over the summer before he graduates. It wouldn't necessarily be for "credit" but I just really like the book and think it will lead to some wonderful conversations.
I hope my plans helped in some way. Only you know your child best and can decide how to modify things. Since my son is only 10 and in 5th grade, a lot can change in 3 years. But currently, after seeing all of the resources that Carrie scheduled, and deciding which ones were the most important to me, this is my tentative plan. I try my best to modify as little as possible. Too much modifications and then it seems like my day is complete out of whack. My craziest year will probably be 9th grade and 10th grade will be a close second. But I think this is extremely do able for me. I like having my kids do things with their siblings at times. And I really like the thought of my son doing stuff with his older sister if he isn't doing things with his younger sister. This saves me teaching time and that is what I desire most.
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