I feel ur pain, although we r just starting to homeschool and my girls r not even in kinder yet ive seen other friends who do and its just like u have described.
We plan to use my fathers word or the abeka Bc it is outlined for u and u don't have to come up with everything off the top of ur head. Ur FIL can still do some of the things hes doing and add one of the other criculiums to it. I'm leaning more towards the abeka only Bc my inlaws r totally against homeschooling and I can have it does as if they were in school.
Www.abekaacademy.org has an option to do everything through videos...meaning an instructor is going over each lesson with the child and then they do the assignments. Then u can choose weather u want to send their assignments in to be graded and recorded (just as it would be in public school) or if u want go do that urself.
Almost all private schools use the abeka program Bc the students r usually a grade level ahead. Its easy to follow and she can go at her own pace Gil shes caught up.