I used this simplified rubric all year to help my students understand the main areas of focus when I was grading their writing pieces. These categories align with the CCSS ELA Module Assessments we had in Florida this past year and go along with the grading rubrics for those assessments. The primary and intermediate had slightly different rubrics, but categories were the same so this is aimed at intermediate since I used it with my 3rd graders, but may work just fine for primary, too.
Rubric gives grade for 3 areas and then those average for final grade for the writing piece. 1) Structure/Organization, 2) Comprehension, 3) Standards of English.. then the overall grade.
Students learn what each category represents. With each different style of writing, we talked about what I was looking for to show mastery in each category (since appropriate structure/organization looks different for opinion task v. research-simulation task, for example).
Download is one excel page, with 6 simple rubrics per page. Size is great to quickly cut on paper cutter and staple/tape to their writing pieces.