Explore the evidence

9 of 88 decisions · clear everything

Survives the gold standard Independent, durable, rigorous The debunked shelf Cheap wins For parents at home Famous numbers, deflated Where we admit ignorance The terrain

evidenceall drop D A–B A only

evaluatorany no dev-led independent

durabilityany follow-up ≥1yr ≥2yr

what are these? →

Your situation · from the applicability layer — absence means “not yet assessed,” never “doesn’t apply”

who's delivering

group / setting

cost

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: low

10/1018/48connected:Feedback and formative assessment Mastery learning (teach → test → r Spaced (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: low

7/712/48connected:Interleaving (mixing problem types Math-fact fluency and timed practi Retrieval practice (the testing ef

Spaced (distributed) practice · practice · ages 6–18 · method

Minimal-guidance math trailed every rival in the one multi-curriculum RCT; explicit instruction for strugglers is math's most replicated result.

moderate supportconf: highgc: low

10/1021/48connected:Explicit instruction vs discovery/

Explicit vs reform/constructivist math instruction · math · ages 5–18

Neither acceleration mandates nor delay mandates work — readiness-matched placement does. Push everyone and the median falls; hold everyone back and the top falls.

mixedconf: highgc: low

9/936/48connected:Acceleration and gifted programs School starting age, relative age,

Algebra timing — acceleration mandates, delay mandates, and readiness-based placement · math · ages 11–18

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: low

7/718/48connected:Spaced (distributed) practice Science content sequencing

Interleaving (mixing problem types vs blocking) · practice · ages 10–18 · method

Manipulatives help when bland, guided, and aged ~7–11 — a guided-representation effect, not 'hands-on learning.' Rich, toy-like objects hurt transfer.

moderate supportconf: mediumgc: low

3/36/48

Manipulatives and concrete-representational-abstract (CRA) sequences · math · ages 5–14

Outdoor time prevents myopia from starting (not progressing); screening plus free glasses raises test scores in children who need them. Two claims, both real.

moderate supportconf: mediumgc: low

17/1736/48

Vision — outdoor time against myopia, and screening and correction for achievement · health · ages 4–18 · input

Word-problem solving is its own skill: computation fluency doesn't produce it. Teaching problem schemas explicitly does (~0.25–0.45 SD on trained content).

moderate supportconf: mediumgc: low

7/78/48connected:Math-fact fluency and timed practi Worked examples (studying solution

Word problems, schema instruction, and the conceptual-vs-procedural question · math · ages 6–14

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: low

53/5339/48connected:Placement and mastery diagnosis Mastery learning (teach → test → r Tutoring Class-size reduction

Does educational technology raise learning — CAI, adaptive software, devices, screens, and AI tutors? · edtech · ages 5–18 · structure

Not yet assessed for this question · 2

The URL is the state — any view you build here is a permalink you can hand to someone mid-argument.