The Grade-Level organization has confused many people. You definitely do NOT want to do all the Levels in every grade. The instructional materials in the sections of these books are identical across grade levels; the differences are entirely in the sentences (vocabulary) in the exercises. In other words, you can work in any of the KISS Levels and then, in the following year, start at that year in the next highest Grade Level. 

     For example, suppose you start in third grade with Level One and get through Level 2.1.4 (Palimpsest Patterns).  Because the fifth-grade books are not complete, the next year you can start at KISS Level 2.1.5 (Phrasal Verbs) in the sixth grade book. As of now, many of the Grade-Level books are not complete, but the sixth grade books are. Thus (unless other books are completed before you get to them), you can simply continue, year after year, with the sixth grade books.

Note: Someone once asked why I didn't simply make three sets--for primary grades, for middle school, and for high school. My response was that many KISS exercises are based on the writing of students at each grade level. The new "Ideal Sequence" (also under construction) is specifically designed as one sequence that begins in first grade and each grade builds on that. Students' writing fits nicely in that sequence, so this sequence will be modified to three sets of books (Primary, Middle, and High School) as suggested below.

The printable KISS books (the "doc" links) are available as MS Word documents. If you do not have MS Word (or a program that can open these documents), go to the Microsoft site where you can get a free reader that will let you open and print these books.