Grading a full class set of end-of-unit essays on Tess of the D'Urbervilles is a marathon, and research on scoring shows that fatigue affects judgment. Essays read late in a session may receive harsher or more lenient scores than similar work read earlier, depending on the grader's mood and energy. Recognizing this problem is essential for teachers who want their grades to be fair.

Several biases commonly appear in essay grading. The halo effect occurs when a strong opening paragraph colors the reader's impression of the rest, while contrast effects can make an average essay seem better or worse depending on the one before it. Handwriting, student reputation, and essay length can also influence scores in ways that have nothing to do with quality.

Because these effects are largely unconscious, awareness alone is not enough. Teachers need structural safeguards that reduce the chance of bias affecting results. A few simple practices can make a meaningful difference.

Practical Strategies to Reduce Bias

One of the most effective strategies is to grade anonymously, either by having students submit papers with numbers instead of names or by folding over the cover page. This reduces the influence of your impressions of individual students. It is easy to implement and has a well-documented benefit for fairness.

• Grade anonymously by using student numbers or covering names before reading
• Score one criterion across all essays at a time rather than grading each essay in full
• Take short breaks every ten to fifteen essays to reset your attention
• Reread two anchor essays periodically to recalibrate your sense of each performance level
• Vary the order in which you read essays across sections to avoid systematic position effects

Scoring by Criterion Instead of by Essay

Grading all essays on a single criterion at a time, such as thesis, before moving to the next criterion, reduces the halo effect. Because you are focused on one dimension, a weak conclusion is less likely to influence your assessment of the thesis. This method takes multiple passes but often produces more consistent scores.

The tradeoff is time. Multiple passes through a class set can feel inefficient, though the improvement in consistency may justify it for high-stakes assignments. Teachers can choose to use this approach for major essays and lighter methods for routine work.

Recognizing the Limits of Human Consistency

Even conscientious teachers cannot maintain perfect consistency across dozens of essays. This is not a criticism but a recognition of human limitations. Building checks into the process, such as re-scoring a sample of essays after a break, helps identify drift before it affects final grades.

If you find that your re-scored essays differ significantly from your original scores, that is useful information. It may indicate that your rubric is ambiguous or that your standards shifted during the session. Adjusting your approach based on this evidence improves both accuracy and confidence.

How AI Grading Supports Consistency

AI grading tools do not tire and apply the same rubric criteria to every essay regardless of when it is processed. This makes them useful as a consistency check, particularly for identifying essays whose human scores diverge from the pattern. Teachers can examine these cases and decide which score better reflects the work.

The human role remains central, since the teacher understands the classroom context and the nuances of interpretation. The tool supplies a steady baseline that helps counteract fatigue and bias. Together, they can produce grading that is both fair and thoughtful, even at the end of a long unit.