When preparing for exams, most students default to highlighting and re-reading. It feels productive—you're actively doing something with the material. But research shows these methods are largely ineffective. Active recall, on the other hand, is one of the most powerful study techniques ever discovered.
This guide compares active recall vs. highlighting, showing you which method actually improves exam performance and why.
The Research: Active Recall vs. Highlighting
Key Findings:
- Dunlosky et al. (2013): Practice testing (active recall) received the highest rating for effectiveness ("high utility"), while highlighting received a "low utility" rating.
- Karpicke & Blunt (2011): Students using active recall scored 50% higher on tests than those who highlighted and re-read.
- Roediger & Karpicke (2006): Testing yourself creates stronger memory traces than highlighting, even when you get answers wrong.
- Research consensus: Active recall consistently outperforms highlighting across hundreds of studies.
Why Highlighting Fails
Problems with Highlighting:
- Passive activity: Highlighting doesn't require active engagement with the material. You're just marking text, not processing it deeply.
- Over-highlighting: Most students highlight too much, making it hard to identify what's actually important.
- No testing: Highlighting doesn't test whether you actually understand or remember the material.
- Illusion of learning: Highlighting feels productive but provides minimal learning benefit.
Why Active Recall Works
Benefits of Active Recall:
- Active engagement: Testing yourself forces you to actively retrieve information from memory, strengthening neural pathways.
- Identifies gaps: Active recall immediately shows you what you don't know, allowing focused study.
- Better retention: Research shows active recall improves retention by 50% compared to passive methods.
- Time efficient: Active recall is faster and more effective than highlighting and re-reading.
Direct Comparison
| Aspect | Active Recall | Highlighting |
|---|---|---|
| Effectiveness Rating | High Utility | Low Utility |
| Test Score Improvement | +50% | Minimal |
| Retention Rate | 60-70% | 20-30% |
| Time Efficiency | High | Low |
| Identifies Knowledge Gaps |
How to Use Active Recall for Exams
Methods:
- Flashcards: Test yourself with flashcards. Try to recall the answer before flipping.
- Practice tests: Take practice tests without notes. Review incorrect answers thoroughly.
- Explain out loud: Explain concepts as if teaching someone else. Identify gaps in your understanding.
- Write from memory: After reading, close your book and write down everything you remember.
Learn more: How to Use Active Recall (Complete Guide)
Real-World Example
Highlighting Method
- • Highlight important passages (2 hours)
- • Re-read highlighted sections (1 hour)
- • Total time: 3 hours
- • Retention: 25%
- • Exam score: 72%
Active Recall Method
- • Create flashcards (30 min with AI)
- • Test yourself with flashcards (1 hour)
- • Take practice test (30 min)
- • Total time: 2 hours
- • Retention: 65%
- • Exam score: 88%
The Verdict
The research is clear: active recall is significantly more effective than highlighting for exam preparation. Students using active recall score 50% higher on tests and retain information 2-3x better.
While highlighting feels productive, it's largely ineffective. If you want to improve your exam scores, switch to active recall methods like flashcards, practice tests, and self-explanation.