Syntes: Butler (1988) — comments helped interest and performance; grades, and grades plus comments, undermined them

Källa: Butler, R. (1988 (British Journal of Educational Psychology 58(1), 1–14)). Enhancing and undermining intrinsic motivation: The effects of task-involving and ego-involving evaluation on interest and performance. https://doi.org/10.1111/j.2044-8279.1988.tb00874.x

What the abstract says (read 2026-10-11; full text not read)

• Design: 12 classes, grades 5–6, randomly assigned (by class) to one of three feedback conditions after interesting tasks (one convergent, one divergent) in each of two sessions: ego-involving numerical grades, task-involving individual comments, or both. Interest and performance of 132 randomly selected pupils of high or low achievement measured at pretest, during the manipulation, and at a third session when no further evaluation was expected.
• Results: interest and performance on both tasks, at both achievement levels, were highest after comments, both when further comments were expected and when they were not. Grades and grades plus comments had similar and generally undermining effects on interest and performance; high achievers who received grades kept high interest and convergent thinking when further grades were expected.
• Not verified here: effect sizes. Small cluster-randomised design (12 classes).

Why it is in the library

The classic study behind "comments, not grades" that C4 and the formative-assessment literature (Black & Wiliam 1998) rest on, and it was missing. It also shows something C4 does not state: adding a grade to comments removed the comments' benefit.