The Evidence on Teaching

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
evidencealldrop DA–BA only
evaluatoranyno dev-ledindependent
durabilityanyfollow-up≥1yr≥2yr
what are these? →
sortconfidencerobustfragileA–Z
domain
verdict
confidence
layer
survival prior
Your situation · from the applicability layer — absence means “not yet assessed,” never “doesn’t apply”
who's delivering
group / setting
cost
outcome class

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 typesMath-fact fluency and timed practiRetrieval practice (the testing ef

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

Group within classes or across grades by subject: modest, nearly free wins. Whole-school streaming does nothing, and early between-school tracking harms the bottom.

moderate supportconf: highgc: low
12/1236/48connected:Do career and technical education

Ability grouping and tracking — four practices, four verdicts · grouping · ages 5–18 · structure

Novices learn faster studying solutions than solving problems — then the effect reverses with expertise. Use worked examples early; fade them.

moderate supportconf: mediumgc: low
6/66/48connected:Explicit instruction vs discovery/Word problems, schema instruction,

Worked examples (studying solutions vs solving problems) · instruction-style · ages 10–18 · method

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 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

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: medium
16/1629/48

Homework — effects by age and by dosage · homework · ages 5–18 · structure

Trust the composite; distrust the breakdown. Subtest strengths-and-weaknesses replicate at chance on retest, and most of what people read off a score report is noise.

mixedconf: mediumgc: low
21/2124/48

What a standardized achievement score does and does not license · assessment · ages 5–18 · structure

Not yet assessed for this question · 3

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