Explore the evidence
6 of 88 decisions · clear everything
Survives the gold standardIndependent, durable, rigorousThe debunked shelfCheap winsFor parents at homeFamous numbers, deflatedWhere we admit ignoranceThe terrain
domain
- math6
- reading6
- writing6
- early childhood5
- science5
- arts4
- character4
- health4
- assessment3
- debunked3
- foreign language3
- history civics3
- homeschool3
- practice3
- grouping2
- instruction style2
- motor skills2
- music2
- practical2
- time2
- transfer2
- behavior1
- class size1
- computer science1
- curriculum1
- deliberate practice1
- edtech1
- feedback1
- homework1
- mastery1
- physical development1
- retention1
- school structure1
- sport1
- talent1
- teachers1
- tutoring1
Your situation · from the applicability layer — absence means “not yet assessed,” never “doesn’t apply”
who's delivering
group / setting
outcome class
Testing yourself beats rereading — robust in real classrooms; honest durable size ~0.1–0.3 SD, biggest after delay, thinnest on transfer.
strong supportconf: highgc: low10/1018/48connected:Feedback and formative assessmentMastery learning (teach → test → rSpaced (distributed) practice
Retrieval practice (the testing effect) · practice · ages 8–18 · method
Spacing beats massing at equal total time — the most robust finding in learning science. Space repetitions at ~10–20% of how long you need to remember.
strong supportconf: highgc: low7/712/48connected:Interleaving (mixing problem typesMath-fact fluency and timed practiRetrieval practice (the testing ef
Spaced (distributed) practice · practice · ages 6–18 · method
Physical capacity is about as heritable as cognitive ability (~60%, no shared environment). Whether trainability is a stable trait remains unproven — the skeptics are winning.
strong supportconf: highgc: low14/1436/48connected:How should a school run its classrDoes working-memory or brain trainCan executive function be trained,Does teaching a growth mindset rai+4
Talent and trainability — what is heritable, and what that does not license · talent · ages 4–18 · input
Mixing problem types helps where confusion is the enemy — discriminating similar categories, mixed math practice — and is useless or worse for facts and prose.
moderate supportconf: mediumgc: lowInterleaving (mixing problem types vs blocking) · practice · ages 10–18 · method
The received wisdom that retention is harmful was two measurement errors, not a finding. Fix them and the achievement effect is zero — but the grade at which you hold a child back decides everything.
mixedconf: mediumgc: low19/1936/48
Grade retention — holding a child back versus promoting, and test-based promotion policies · retention · ages 5–18 · structure
Near-zero in primary and almost entirely correlational in secondary. The causal base is three small trials; what the homework IS beats how much of it there is.
mixedconf: mediumgc: medium16/1629/48
Homework — effects by age and by dosage · homework · ages 5–18 · structure
The URL is the state — any view you build here is a permalink you can hand to someone mid-argument.