How does this work? Why not use grade levels?

I originally intended to use grade level numbers, but I have shifted to using curricula with age- and grade-independent titles, much like a textbook or computer game might have. This allows students to have the social ease of being in the same grade as their age-peers (to make interactions with neighbors, testers, school districts, homeschool groups, and grocery store clerks a little smoother), but not limited to studying what their age-peers are studying.

There are several benefits of divorcing the content a child learns from their age/grade level:

They child can go through the curriculum as quickly or slowly as they want without having to worry about "jumping ahead" or "Falling behind." There is no "ahead" or "behind" this way--only learning.

You can start mid-year, in the summer, after a break, when you suddenly discover you really are homeschooling even though it's now November because you have just pulled your kids out of their public classrooms, or whenever, and still start at the beginning and get all the information, do all the activities, etc.

Nobody misses learning something cool or exciting (or vital) simply because the calendar said we're done with school for the year--you can pick up where you left off regardless of what grade the child has moved up to.

What I use for, say, Kindergarten might be too hard for your child. Instead of embarrassing them by "holding them back" a grade, you can put them where they belong, and it's just right (not "ahead" or "behind").

You can do the last seven curricula in any order, provided your child is mature enough to handle the literature. The content is, on the whole, not leveled the way most other curricula are. More akin to high school or college, the information is grouped by subject rather than by average intellectual ability level. Since biology is neither harder nor easier than chemistry--just different--you can choose which curriculum to delve into next based on your child's interests, rather than an arbitrary age-level decision made by someone else. If you finish all ten curricula, you will have taken your child from age 1 to age 13 and they will have learned everything the public school children learn and more--but it doesn't matter what order you do the last seven "levels". (Be aware, though, that even highly gifted 7 year olds will likely need more coaching than 13 year olds, and that some of the activities, like coloring pages, might not appeal to all children. Skip them.)