Report card grades are designed to be an indicator of your child's performance at school during a given time period and are useful tools in diagnosing any needs your child may have or changes that may need to be made to help them be their most successful. If you have read the report card grading system in the past, you are aware of the numeric system and what it means:
    4 = Exceeding expectations
    3+ = Strongly meeting expectations
    3 = Meeting expectations 
    2 = Approaching expectations
    1 = Needs improvement
    These numbers can mean different things in different subjects, since subjects like math are based on test averages and subjects like writing or social studies are often based more on rubrics. No matter the subject, however, a score of 4 is not automatically handed out for an assignment, project, etc. just because it is completed. I do not start with a 4 and then deduct from it for everything "wrong." A 4 means Exceeding Expectations; a 3 means Meeting Expectations. So in any given assignment, project, etc, assume that a child should/will be earning a 3 or 3+ unless their work is incomplete in some way (in which case, a 2 has been earned) or their work has exceeded the basic requirements set down. With any assignment/project, I even provide a list of suggestions on ways children can enhance their work and earn a 4 if they choose to put in the extra effort; they are additions to the basic requirements. 
    Just remember that a 3 does not mean incomplete, or that there is anything "wrong" with your child's work. 
    Report card grades for math are based on test scores and are broken down as follows: 94% = 4, 90%-93% = 3+, 80%-89% = 3, 70%-79% = 2, below a 69% = 1
    Report card grades are based on projects, tests, and in-class assignments. Your child has a different teacher and a different science topic to learn each marking period; they could be very good at one topic and possibly struggle with another. 
    Social Studies:  
    Report card grades are based on projects, tests, and in-class assignments. 
    Report card grades are based on the number of books a child "free-reads" and then completes a log sheet for each marking period. Each book must average 200 pages, so a large book like Harry Potter books, which can be between 400 - 600 pages are worth 2 or 3 books. This encourages children to pick a book they enjoy which is on their reading level, since they always receive credit for everything they have read. Reading 5 books (1,000 pages) per marking period is the minimum needed to earn a 3; any fewer will result in a grade of 2 or 1. Reading 7 books will earn a 3+ and 10 books earns the child a 4.    
    Report cards reflect the work of a whole marking period of practice and workshopping, culminating in one final writing assignment each marking period. Grades may fluctuate from marking period to marking period depending on the type of writing we have focused on for each one. For example, a child who can write excellent stories may have trouble with a research paper.