The science
How understanding actually forms.
Decades of research, in four charts.
What makes learning stick
Average effect size · 0.4 ≈ 66th percentile
| Technique | Average effect size |
|---|---|
| Recalling, not re-reading | 0.50–0.61 |
| Explaining in your own words | 0.55 |
| Feedback that explains why | 0.48 |
| Mixing problem types | 0.42 |
| Refuting misconceptions | 0.41 |
| Working it out, not reading it | 0.40 |
| Trying before being taught | ≈0.36–0.58 |
AI that answers vs. AI that asks.
Later exam score, vs. no AI
| Group | Later exam score, vs. no AI |
|---|---|
| AI that answers | −0.19 SD |
| AI that guides | −0.01 SD · about the same as no AI |
Learning gains, and time it took
| Group | Learning gains · time |
|---|---|
| Excellent active-learning class | 1× · 75 min |
| AI tutor that only asked | 2×+ · 49 min |
Why we come back
Illustration, not data
How well you remember
No re-checks
1 day3 days7 days14 days
How well you remember
No re-checks
1 day3 days7 days14 days
Inside your brain.
You have to produce itGenerated beats given.
New sticks to oldPrior knowledge speeds memory.
Spacing is biologySpread practice makes it last.
Sleep does the filingOvernight, learning settles in.
Curiosity opens the doorWanting to know helps it stick.
Surprise rewiresConfident mistakes fix best.
What we don't claim.
We don't model your neurons.
We don't sort you into “learning styles.”
We don't inflate results.
Sources
- Adesope et al. (2017). Practice testing.
- Bastani et al. (2025). PNAS.
- Bertsch et al. (2007). The generation effect.
- Bisra et al. (2018). Self-explanation.
- Brunmair & Richter (2019). Interleaved learning.
- Cepeda et al. (2008). Spacing effects.
- Dunlosky et al. (2013). Effective learning techniques.
- Gruber et al. (2014). Curiosity and memory. Neuron.
- Kestin et al. (2025). Scientific Reports.
- Pashler et al. (2008). Learning styles.
- Rowland (2014). The testing effect.
- Sinha & Kapur (2021). Productive failure.
- Smolen et al. (2016). Nature Reviews Neuroscience.
- Tse et al. (2007). Schemas and consolidation. Science.
- Wisniewski et al. (2020). Feedback.
