Why AI grading is more consistent than human marking

The problem with human marking

Every teacher knows the challenge: you mark 30 essays on Friday evening, and by essay 20, your standards have drifted. Research from Ofqual has shown that marker agreement rates on extended-response questions can be as low as 56%.

This isn't a failure of teachers — it's a limitation of human cognition. Fatigue, mood, and anchoring effects all influence scores.

How AI grading works differently

ExAIm uses Claude by Anthropic to grade student responses. The AI applies the same mark scheme criteria to every answer, every time. It doesn't get tired. It doesn't anchor to the previous response.

For each answer, the AI:

Consistency at scale

A teacher marking 30 biology essays might take 3–4 hours. ExAIm grades them in under 2 minutes. More importantly, essay #30 gets exactly the same attention as essay #1.

AI grading is a tool, not a replacement

We built ExAIm to support teachers, not replace them. AI grading handles the repetitive marking load so teachers can focus on intervention — identifying which students need help and providing it.

The teacher remains in control. They can review any AI-graded response, override scores, and add their own comments.