A short online lesson teaching that intellectual ability can be developed (a growth-mindset intervention) raises the grades of lower-achieving secondary-school students by a small amount, but does little for students on average; that struggling students gain more than other students is not established across studies: in a meta-analysis of 63 studies, samples with low grades or at risk of failing gained about 0.07 standard deviations (0.09 in studies that checked the lesson changed mindsets), not significantly more than other students, and the best-designed studies were too few to check (Macnamara & Burgoyne 2023), although the largest preregistered trial did test it and found a larger gain for students in the lower half of their school's grades than for the upper half (about 0.10 against 0.01 grade points; difference P = .034; Yeager et al. 2019).
Status
weakened
Last change
2026-11-06
Serves
Q1
Ages
grundskola-hog, gymnasium
Area
Motivation and curiosity
Bounds
Short (about an hour or less), standalone growth-mindset interventions in secondary school, outcome grades or achievement; not praise or feedback in general (C4), not long-term programmes. Evidence on file: Yeager et al. 2019 (Nature; preregistered national US trial; grades improved for lower-achieving students, context-dependent on peer norms; correction 2026-10-19: "lower-achieving" there means at or below the school-specific median GPA, half of all students, not low achievers in absolute terms; core-course GPA at the end of ninth grade +0.10 grade points for them (95% CI 0.04 to 0.16), +0.01 for higher achievers (P = 0.634), intervention × lower-achiever interaction B = 0.09 (95% CI 0.01 to 0.17, P = 0.034; Extended Data Table 1 legend); grades followed only to the end of ninth grade); Sisk et al. 2018 (two meta-analyses; intervention meta k = 43, N = 57,155; overall effects weak, possible benefit for low-SES or at-risk students). Differential bound (2026-10-16; enriched 2026-11-06): Macnamara & Burgoyne 2023 (Psychological Bulletin; 63 studies, N = 97,672) coded academic challenge as a preregistered moderator: high-challenge samples d = 0.07 [0.01, 0.13], low-challenge 0.05, difference ns (Q(2) = 0.28, p = .870); high-challenge levels pool children, adolescents and adults. The secondary-school–relevant developmental cell is adolescents d̄ = 0.04, 95% CI [0.002, 0.09], p = .041 (Table 7; Q(2) across ages = 0.47, ns). Meta-Analysis 3's "highest-quality" set (6 studies, N = 13,571, overall d̄ = 0.02 [−0.06, 0.10]) rests on a bar lowered to ≥60% of the authors' 10 best-practice criteria, because zero mindset-shifting studies met every criterion (p. 28). Macnamara & Burgoyne write that Yeager et al. 2019 did not report a test of whether lower achievers' effect differed from higher achievers'; the trial's Extended Data Table 1 legend does report it (see above), so the "not established" clause rests on the meta-analysis's between-study moderator test, not on an absence of within-trial tests (corrected 2026-10-19).
What would kill this
A large preregistered randomised trial or meta-analysis of short growth-mindset interventions finds no grade gain for lower-achieving or at-risk secondary-school students. Promoted from K31 on 2026-10-16 in the broadening Jonatan approved 2026-10-16 (one new claim per uncovered area.
Tutor consequence
none yet
Attack record
1 attack: 1 narrowed
2026-10-16 narrowed
Attack
A preregistered meta-analysis of 63 growth-mindset intervention studies (N = 97,672) tested whether the effect depends on students' level of academic challenge and found it does not: samples where most students had low grades or were at risk of failing gained d = 0.07 (95 % CI 0.01 to 0.13), against 0.05 for low-challenge samples, a nonsignificant difference (Q(2) = 0.28, p = .870); the same held among studies showing the lesson changed mindsets (high challenge 0.09, Q(2) = 2.98, p = .226), and the best-designed studies (6 studies, overall d = 0.02, ns) were too few to test it, so C13's contrast — a gain for lower achievers while little happens on average — is not established.
Target
claim-text
Source
Macnamara & Burgoyne 2023 | Psychological Bulletin 149, DOI 10.1037/bul0000352
Steelmans to
C13's distinguishing assertion is that short mindset lessons help lower-achieving students specifically even though the average effect is small; the largest meta-analysis to date coded exactly this moderator in advance and found no difference by challenge level, and its authors call the evidence for the struggling-students argument "limited" (p. 31).
Why
Run ordered 2026-10-16 after Jonatan supplied the full text. Full text read (APA Online First PDF, supplied by Jonatan 2026-10-16, stored privately in the source folder). Coding (p. 14): high challenge = most of the sample had low grades or was otherwise at risk of failing; moderate = situational challenge (new school, stereotype threat); low = no risk indicators; run with full samples and with available high-challenge subsamples swapped in. Meta-analysis 1, all studies (Table 7, p. 22): high d = 0.07 [0.01, 0.13] (p = .019), moderate 0.05 [−0.02, 0.12], low 0.05 [−0.01, 0.11]; Q(2) = 0.28, p = .870; unchanged with subsample replacement (2 studies). Overall d = 0.05 [0.02, 0.09], nonsignificant after correcting for publication bias (abstract). Meta-analysis 2, studies with a successful mindset manipulation check, 13 studies (Table 13, p. 27): high 0.09 [0.04, 0.14] (p < .001), moderate −0.01 [−0.10, 0.09], low 0.05 [−0.21, 0.32]; Q(2) = 2.98, p = .226. Meta-analysis 3 (6 studies, N = 13,571, best practices): d = 0.02 [−0.06, 0.10]; no moderator analyses possible. The authors note Yeager et al. 2019 reported only below-median students without testing the difference from other students (p. 11). Kill withheld: high-challenge subgroups do show a small positive pooled effect in two of the three analyses; challenge categories pool children, adolescents and adults and are not limited to secondary school; subgroup estimates are not bias-corrected. Not a restatement: C13's Bounds cite Sisk et al. 2018 for weak overall effects and a possible at-risk benefit; nothing on the claim said the lower-achiever benefit was not larger than for others. Not a preprint. Claim, Bounds and Status rewritten same turn; brief and the practical rule updated.
Rewrite
claim-field+brief
Corrections to our notes
These fix a number or a fact in our notes. They are not attacks and do not count toward the floor of 3 survivals.
— The preregistered national US trial that C13's lower-achiever clause leans on did test whether lower achievers gained more than other students and found they did (higher achievers B = 0.01 grade points, P = 0.634; intervention × lower-achiever interaction B = 0.09, 95% CI 0.01 to 0.17, P = 0.034, n = 12,490), so the statement relayed from Macnamara & Burgoyne 2023 that this trial never ran the test is wrong, and…
— Checked against the full text of the study: precision of the Macnamara differential and best-evidence lines.
Meta-analysis of 53 randomised samples: for academic achievement in subsamples expected to benefit most, with high implementation fidelity, d = 0.14 [0.06, 0.22], prediction interval −0.08 to 0.35. Targeted subsamples are broader than lower-achieving secondary students; not only online lessons. Abstract only.
EEF Year 6 English effectiveness RCT (101 schools): KS2 maths/reading/GPS ≈ 0; FSM subgroup also null; control teachers often already used similar messages. Primary multi-week teacher-led programme — outside C13 short online secondary scope; average-effect context only. Full text stored.
Quality-graded review of school RCTs: the most trustworthy trials show whole-sample effects of d = −0.01 to 0.065 (Peru, Norway, rural China, England, Argentina). Studies reporting only lower-achiever or at-risk subgroups (Yeager et al. 2019, Paunesku et al. 2015) were excluded, so it does not test C13's lower-achiever clause; consistent with 'does little on average'. Full text read.
School-randomised trial in 800 Peruvian secondary schools (working paper, preprint flag): one 90-minute teacher-led paper session raised maths by about 0.05 SD overall, about 0.13 SD in the lower-scoring regional sample and about zero in Lima; regional gains persisted at 14 months. Not an online lesson and no split by individual prior achievement. Full text read.