Explore the evidence
5 of 88 decisions · 1 collapse at your settings · clear everything
Survives the gold standardIndependent, durable, rigorousThe debunked shelfCheap winsFor parents at homeFamous numbers, deflatedWhere we admit ignoranceThe terrain
domain
Your situation · from the applicability layer — absence means “not yet assessed,” never “doesn’t apply”
group / setting
outcome class
Growth-mindset interventions change beliefs almost everywhere and change achievement almost nowhere: the two independent national-scale trials measured standardized tests and found exactly zero.
mixedconf: highgc: low10/1829/48connected:FadeoutSystematic/explicit phonics vs whoTalent and trainabilityAre self-control and grit teachabl
Does teaching a growth mindset raise achievement? · character · ages 4–18
Sentence combining improves writing where grammar teaching fails — the same meta-analyses score them +0.50 and −0.32.
moderate supportconf: mediumgc: low2/89/48connected:Does teaching grammar improve chilDoes teaching movement transfer toDoes handwriting and transcriptionDoes teaching spelling work, and w
Does sentence combining improve writing? · writing · ages 5–18
Sort by what the software replaces: adaptive drill inside the school day buys +0.05-0.20 SD; a device, a connection or the teacher buys zero to negative; LLM tutors have no usable evidence at all.
mixedconf: mediumgc: low24/5339/48connected:Placement and mastery diagnosisMastery learning (teach → test → rTutoringClass-size reduction
Does educational technology raise learning — CAI, adaptive software, devices, screens, and AI tutors? · edtech · ages 5–18 · structure
Conceptual-change teaching reliably moves the test and nothing shows it removes the intuition. Corrected for design and publication bias, a taught unit is g≈0.64 and a refutation text g≈0.28.
mixedconf: mediumgc: lowinsufficient at your settingsScience misconceptions and conceptual change — can naive intuitions be taught away? · science · ages 6–18
Coaching buys ~0.25 SD of score and has for 42 years — a fraction of what's advertised — and none of it is ability. The score moves; the construct doesn't.
mixedconf: mediumgc: medium4/2036/48
Test preparation — does coaching raise scores, and does a raised score mean raised ability? · assessment · ages 5–18 · structure
Not yet assessed for this question · 46
- Acceleration and gifted programs — the label vs the content
- Algebra timing — acceleration mandates, delay mandates, and readiness-based placement
- Does arts education raise academic achievement?
- Chronic absenteeism — does raising attendance raise achievement?
- Background knowledge and vocabulary as drivers of reading comprehension
- Does working-memory or brain training transfer to intelligence and achievement?
- Class-size reduction
- Curriculum choice as a school-level lever
- Deliberate practice and the 10,000-hour rule
- Physical activity as an input — dose, fitness, and school outcomes
- Explicit instruction vs discovery/inquiry — how much guidance?
- Explicit vs reform/constructivist math instruction
- Fadeout — why early gains disappear, and what actually persists
- Feedback and formative assessment
- Ability grouping and tracking — four practices, four verdicts
- The early home environment — what parents can and cannot causally move
- Interleaving (mixing problem types vs blocking)
- Does matching instruction to a child's "learning style" improve learning?
- Manipulatives and concrete-representational-abstract (CRA) sequences
- Mastery learning (teach → test → reteach to criterion → advance)
- Math curriculum choice — how much does the textbook matter?
- Math-fact fluency and timed practice (and the anti-timed-test claims)
- Brain Gym, Whole Brain Teaching, and the smaller classroom brain fads
- Does teaching movement transfer to cognition, achievement, or lifelong activity?
- Feedback frequency and mental practice in motor learning
- Practice scheduling for motor skills — varied vs blocked, spaced vs massed
- Should Gardner's multiple intelligences be used as a basis for instruction?
- Breakfast, school meals, and micronutrients — what feeding children actually buys
- Phonemic awareness training (and whether it needs letters)
- Systematic/explicit phonics vs whole language and balanced literacy
- Preschool at scale — Head Start, state pre-K, and what universal provision delivers
- Perry Preschool and Abecedarian — what the famous studies actually establish
- Reading-comprehension strategy instruction (reciprocal teaching, summarizing, questioning)
- Reading fluency — guided repeated oral reading, and whether repetition matters
- Reading Recovery and Tier-2 1:1 early-literacy tutoring
- Retrieval practice (the testing effect)
- School spending, charters, and what school-level choices actually move outcomes
- School starting age, relative age, and academic redshirting
- Spaced (distributed) practice
- Talent and trainability — what is heritable, and what that does not license
- Teacher quality — selection over credentials and workshops
- Tutoring — the honest effect, the Bloom 2-sigma myth, and what survives scale
- Vision — outdoor time against myopia, and screening and correction for achievement
- Word problems, schema instruction, and the conceptual-vs-procedural question
- Worked examples (studying solutions vs solving problems)
- Early sport specialization, talent selection, and the relative age effect
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