With a rubric, the teacher writes down the various features in a standard paper, such as the style, tone and content, and then rates the student on the extent to which they succeeded or failed at specific tasks. The rating is often a number, since these are easier to add than letters, though the rating can be a letter grade. For example, a student may receive a maximum of 7 points for the essay's grammar. Students with spotless grammar receive 7/7, a student with a few errors may receive a 4/7 and a paper riddled with errors may receive a 1/7.
The teacher adds up all the points and assigns a letter grade based on the percentage of points the student received, compared to the maximum number of points. For example, when the cumulative number of points adds up to 64/100, the student receives a 64%, which is a D.
Rubrics consider how multiple factors come together to create a successful paper. A student may excel at logical argumentation and research but not know how to use a semicolon. The rubric helps the teacher give the student a grade that reflects her writing competency. Rubrics help teachers let students know what they must work on in their writing. When the student sees that she received a low score for her conclusion, she will know that she needs to work on strengthening her conclusions.
Rubrics help the teacher justify a grade to a student and possibly to school administrators. The rubric shows exactly what factors the teacher considered when giving the student a grade. Then, the teacher can show where the student deviated from expectations.
Rubrics slow down teachers and force them to look at all aspects of the paper. Teachers may feel tempted to quickly assign a grade to a paper, allowing them to get through grading more quickly. This can lead to unfair grading, since the teacher is more likely to focus on localized elements, which can lead to biased grading. However, rubrics can also speed up grading, since they reminds teachers of which elements they intended to focus on.
Classes may vary in what they focus on, especially remedial writing classes. Teachers often seek to teach students specific principals, such as how to properly cite sources. Teachers can weigh certain factors more heavily, having the reference page count for six points and grammar can only count for two points, encouraging students to spend more time learning to properly cite sources. The best rubrics are specific to the assignment.