Generated view: 11 sources whose Kunskapsbank note was filed under this theme, and the claims and candidates they link to.
C27 weakened
Assigned homework goes with higher achievement, and in correlational studies the link is clearly stronger for pupils in grades 7–12 than in grades K–6, where it is small; but the small early-grade link has not been shown to mean a small effect: in the few experiments, classes given homework scored higher than classes without it, and in a systematic review whose homework-versus-none experiments were mostly in grades 3–6 (6 of 10; 4 in grades 7–12) the gain was about 0.45 standard deviations (mostly old studies at moderate to critical risk of bias; Guo et al. 2024).
Serves: Q1 (How do humans actually learn, and what helps them learn best?)
Ages: grundskola-lag, grundskola-hog, gymnasium
Bounds: Assigned homework and achievement; most evidence is correlational, and the size depends on how homework is measured (students' own reports gave stronger links). Evidence on file: Cooper, Robinson & Patall 2006 (Review of Educational Research, DOI 10.3102/00346543076001001; full text): generally consistent positive influence across designs; correlations stronger in grades 7–12 than K–6; five experiments with usable effects gave a mean d ≈ .60 on unit tests (95% CI about .38–.82), with design and unit-of-analysis limits. Fan, Xu, Cai, He & Fan 2017 (Educational Research Review 20, DOI 10.1016/j.edurev.2016.11.003; abstract/secondary summary only, flagged): maths and science r ≈ .22; numbers must be checked in the paper before any ledger use. Weakened 2026-11-03 (nightly attack): Guo, Li, Xu, Hu, Liu, Xing, Li, White & Yang 2024 (Campbell Systematic Reviews 20(3), e1431, DOI 10.1002/cl2.1431; open access, full text read): 11 controlled studies of homework versus no homework (2 RCTs, both at high risk of bias; 9 non-randomised, 4 moderate, 2 serious and 3 critical risk of bias; most published 1939–1995; only one with a follow-up); pooled g = 0.45 (95% CI 0.24–0.66; 14 comparisons; I² = 71%), arithmetic computation g = 0.46, problem solving g = 0.17, concepts not significant; the 14 homework-versus-none comparisons come from 10 studies published 1939–1995 in grades 3 (2 studies), 4–6 (1), 5 (1), 6 (2), 7 (1; Foran & Weber 1939), 8 (1; Ewart Anderson 1946) and senior high-school English (2; McGrath 1992, Tupesis 1972), so 6 of 10 in grades 3–6 and 4 in grades 7–12; the grade-2 randomised trial (Dolean & Lervåg 2021), the only study with a follow-up, compared more with less homework and is not in the pooled g; no grade-level subgroup analysis was possible (corrected 2026-11-04 against Table 2 and §5.3.1; the earlier "of the 8 studies that reported grade, 7 were in grades 2–6 and 1 in grade 8" was wrong). The review's RCT labels differ between §5.2.1 and Table 2; Egger's test p = 0.06. So the grade 7–12 versus K–6 contrast rests on correlations; the experimental evidence, though weak, is mostly from primary school and does not show a small effect there.
Attack record: 1 attack: 1 narrowed · Evidence links: 4 linked sources (2 supports, 2 limits)
4 link(s) from sources in this view.
C28 weakened
Curriculum-linked learning outside the classroom (field trips, museum visits, outdoor teaching) raises school achievement compared with teaching the same content only in the classroom, by about 0.3 standard deviations in randomised studies (about 0.5 across all studies, inflated by non-randomised ones), and more in primary school than later.
Serves: Q1 (How do humans actually learn, and what helps them learn best?)
Ages: grundskola-lag, grundskola-hog, gymnasium
Bounds: Structured, curriculum-linked activities outside the classroom; not homework (C27) and not unstructured leisure. Evidence on file: Delen et al. 2026 (Sustainability 18(3), 1437, DOI 10.3390/su18031437; full text read 2026-11-08, open access): 42 studies (1970–2022), 54 effect sizes; overall g = 0.529 (95% CI 0.392 to 0.665; Q = 744.8, df 53); by design (Table 3), randomised studies g = 0.307 (0.167 to 0.447, k = 29) vs non-randomised g = 1.020 (0.722 to 1.318, k = 16), and the authors say stronger claims should rest mainly on randomised or well-controlled studies; by region, North America g = 0.149 (−0.010 to 0.308, k = 15) and Scandinavia g = 0.180 (−0.093 to 0.454, k = 4), against Türkiye 1.023 (k = 11); by subject, science 0.632, social science 0.757, maths 0.295, reading 0.166; by level, elementary 0.805, middle 0.617, secondary 0.500 (grade slope −0.136, p = .002; subgroups not adjusted for design); exposures of 2–6 hours g = 0.034 (−0.163 to 0.230, k = 7). The meta-analysis does not code or report test delay, so durability is not addressed; its assessment-item-type figures differ between Table 3 and the text. Holmes 2011 (Learning Environments Research, DOI 10.1007/s10984-011-9094-y; abstract only): 228 grade-6 pupils randomly assigned to control, museum exhibit, lesson or both; the exhibit group gained, but no lasting differences between groups were shown — a warning on durability. A bold claim: the size rests on one meta-analysis, now read in full; the half-SD average is not the randomised estimate. Regular weekly outdoor teaching (udeskole-type), full text of Becker et al. 2017 (IJERPH 14(5) 485, DOI 10.3390/ijerph14050485; §3, Tables 1–3): a systematic review of 13 studies found no randomised trial, one controlled study with standardised tests (a one-year out-of-school science programme for fifth graders; reading and writing higher than controls, p = 0.03, no effect size given, maths not reported) and no delayed achievement tests.
Attack record: 1 attack: 1 narrowed · Evidence links: 7 linked sources (3 supports, 3 limits, 1 challenges)
7 link(s) from sources in this view.