Syntes: Qin & Wang (2026) — more homework time helped grade-8 maths only where homework quality was low, and went with less interest

Källa: Qin, K. & Wang, Y. (2026). Time and quality in and out of class: the roles of instruction and homework in mathematics achievement and interest. Frontiers in Psychology 17 (2026). https://doi.org/10.3389/fpsyg.2026.1870861

Verified content

• [abstract] 2,808 grade-8 pupils, 76 schools, China; self-reported homework time in four bands and homework quality, plus a maths test; multilevel models controlling for sex and SES.
• [full text] With low perceived homework quality, 60–90 minutes of homework went with higher maths scores than 30 minutes or less; the homework-time-by-quality interaction was β = −0.05 (p < .01), and under high quality more time was even negatively associated with achievement.
• [full text] On average, only 30–60 minutes of daily maths homework went with higher scores than 30 minutes or less (β = 0.06, p < .01); 60–90 and over 90 minutes did not (β = 0.01 each). The homework-time block added 0.3% of within-school variance and the time-by-quality terms another 0.3%; instructional clarity added 2.9% (Table 1).
• [full text] Between-school effects were non-significant or practically negligible; the authors warn that several significant terms explain very little variance.
• [full text] Maths interest went with homework quality (β = 0.41, p < .001; 8.4% of variance). The abstract also says interest was negatively related to homework time, but once homework quality is in the model no homework-time category is significant, and the authors write that homework time "was not associated with students' mathematics interest" (Table 2, section 5.2). (Corrected 2026-11-02 by study mining; the earlier version of this note followed the abstract.)

Limits

• [assessment] Cross-sectional and self-reported (Harman test passed, but the authors say method bias cannot be ruled out); one country; about time, not whether homework is assigned.
• [assessment] Relevant to C27's grades 7–12 link: within grade 8, how much homework time goes with scores depends on its quality, and the time effects are tiny; it cannot test C27's grade contrast.

Why it is in the library

A large 2026 study in C27's strongest age band that splits homework time from homework quality, the distinction the C27 meta-analyses blur.

Added 2026-11-01 by the project (weekly source sweep, kind: new; read: full text). [abstract] = from the published abstract; [full text] = read in the full text; [assessment] = the project's own assessment.