Syntes: Koenka et al. (2021) — grades beat no feedback on achievement, but comments beat grades

Källa: Koenka, A. C.; Linnenbrink-Garcia, L.; Moshontz, H.; Atkinson, K. M.; Sanchez, C. E.; Cooper, H. (2021 (Educational Psychology 41(7), 922–947; online 2019-11-09)). A meta-analysis on the impact of grades and comments on academic motivation and achievement: a case for written feedback. https://doi.org/10.1080/01443410.2019.1659939

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

• Scope: elementary and secondary school; four meta-analyses: (a) grades vs no performance feedback and (b) grades vs comments, each on academic motivation and on achievement.
• Results: compared with no feedback, grades raised achievement but lowered motivation. Compared with comments, students receiving grades had poorer achievement and less optimal motivation.
• Moderators: effects varied by type of motivation, context (subject, comment type), student characteristics (achievement level) and method (anticipating versus receiving a grade); not all moderators could be tested.
• Not verified here: effect sizes, whether achievement was measured with a delay, and what kinds of comments were included. Earlier mention: nightly run 2026-10-07 found this study while searching C4 (supports; not added to the library then).

Why it is in the library

The standard school-age meta-analysis on grades versus comments, directly on C4. It supports C4's comparison (comments over grades on achievement) and adds a nuance C4 does not state: grades alone are better than no feedback for achievement.