Explore the evidence
12 of 88 decisions · clear everything
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- foreign language3
- history civics3
- homeschool3
- practice3
- grouping2
- instruction style2
- motor skills2
- music2
- practical2
- time2
- transfer2
- behavior1
- class size1
- computer science1
- curriculum1
- deliberate practice1
- edtech1
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Matching instruction to 'learning styles' does nothing: real matching experiments return d=.04. The correlational literature IS the myth.
debunkedconf: highgc: lowDoes matching instruction to a child's "learning style" improve learning? · debunked · ages 4–18 · debunked
Teaching handwriting works and transfers: freeing the hand frees composition, with gains still present at six months — even taught in groups of three.
moderate supportconf: mediumgc: mediumDoes handwriting and transcription instruction matter, and should young children type instead? · writing · ages 5–12
Sentence combining improves writing where grammar teaching fails — the same meta-analyses score them +0.50 and −0.32.
moderate supportconf: mediumgc: lowDoes sentence combining improve writing? · writing · ages 5–18
Strategy instruction is writing's best-supported method — at roughly a fifth of its advertised size once measures are independent (d≈0.8 → ~0.15).
moderate supportconf: mediumgc: lowDoes strategy instruction (SRSD, the writing process) improve writing? · writing · ages 5–18
Formal spelling instruction works (ES 0.54) and more formal beats less formal — explicit wins again, and it transfers beyond spelling itself.
moderate supportconf: mediumgc: lowDoes teaching spelling work, and what does it transfer to? · writing · ages 5–18
Capitalisation and punctuation move when directly taught and directly measured, and don't move when embedded in writing programmes. A teachable subject, not a writing lever.
mixedconf: mediumgc: mediumCan capitalisation, punctuation and usage be taught directly as their own subject? · writing · ages 5–18
A missed day costs little (~0.005 SD); interventions reliably buy days back cheaply, but nobody has shown the recovered days move achievement.
mixedconf: mediumgc: mediumChronic absenteeism — does raising attendance raise achievement? · time · ages 4–18 · input
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: lowDoes educational technology raise learning — CAI, adaptive software, devices, screens, and AI tutors? · edtech · ages 5–18 · structure
Taking time away hurts measurably; adding it back buys almost nothing. The return per hour is ~0.02-0.03 SD, concave, and near zero in disorderly classrooms.
mixedconf: mediumgc: lowLength of the school day and year, time-on-task, extended time, and summer · time · ages 4–18 · structure
Never operationalised well enough to test: no MI-based trial meets even a loose evidential bar. Four decades in, a valid evaluation is still impossible.
insufficientconf: mediumgc: mediumShould Gardner's multiple intelligences be used as a basis for instruction? · debunked · ages 4–18 · debunked
Teaching grammar does not improve writing at any age tested — and it displaces the things that do.
negativeconf: mediumgc: lowDoes teaching grammar improve children's writing? · writing · ages 5–18
Brain Gym, Fast ForWord, coloured overlays, the Mozart effect: tested and failed, or never evidence-based at all. Mozart works exactly as well as any other music.
debunkedconf: mediumgc: lowBrain Gym, Whole Brain Teaching, and the smaller classroom brain fads · debunked · ages 4–18 · debunked
The URL is the state — any view you build here is a permalink you can hand to someone mid-argument.