I found this great new book called, "How To Grade For Learning, Linking Grades to Standards" by Ken O'Connor. It's specifically focused on middle and high school.
He uses these guidelines for grading:
1) Relate grading procedures to learning goals (standards)
2) Use criterion referenced performance standards as reference points to determine grades (grading rubric)
3) Limit the valued attributes included in grades to individual achievement
4) Sample student performance - do not include all scores in grades
5) Grade in pencil - keep records so they can be updated easily
6) Crunch numbers carefully - if at all
7) Use quality assessments and properly recorded evidence of achievement
8) Discuss and involve students in assessment, including grading, throughout the teaching/learning process
In this book the author says that we should not grade formative assessments, only summative assessments. He goes on to say that teachers should provide feedback on formative assessments, but because they are "formative" - it would be unfair to grade them. He says, "What does count for grades are the performances that students give to demonstrate the knowledge, skills, and behaviors they have acquired as a result of instruction and practice." He says that teachers should have some record keeping mechanism form both summative and formative assessments, but the grade includes only summative assessment scores.
The book is filled with checklists and grade book examples.
Here's another quote that is helpful in focusing our work:
"In order to have grades that have real, not just symbolic, meaning, and enable us to focus on learning, not grades, grading must be seen not just as a numerical, mechanical exercise, but as an exercise in professional judgement."