| 01 | The scientific method | 88.9 |
| 02 | Evolution | 61.1 |
| 03 | Genetics and inheritance | 37.6 |
| 04 | Forces and motion | 33.5 |
| 05 | Observation and measurement | 30.0 |
| 06 | Energy | 29.1 |
| 07 | Cause and effect | 20.3 |
| 08 | Relativity (Special & General) | 19.9 |
| 09 | Matter and Its States | 19.2 |
| 10 | Models | 18.7 |
| 11 | Statistics, Probability, and Uncertainty | 18.2 |
| 12 | Systems and interactions | 17.7 |
| 13 | Atoms and Molecules | 16.9 |
| 14 | Matter and atoms | 16.3 |
| 15 | newscientist.com | 15.6 |
| 16 | Cells and life processes | 15.0 |
| 17 | cells as tiny living factories | 14.7 |
| 18 | Information and uncertainty | 14.4 |
| 19 | Scale | 14.2 |
| 20 | Feedback loops | 14.0 |
| 21 | Entropy and disorder | 13.8 |
| 22 | Conservation of Energy (Thermodynamics) | 13.5 |
| 23 | Photosynthesis | 13.1 |
| 24 | Cellular Respiration | 12.8 |
| 25 | Atomic Theory and the Nature of Matter | 12.5 |
| 26 | Thermodynamics | 12.0 |
| 27 | thegreatcourses.com | 11.8 |
| 28 | quantum theory | 11.6 |
| 29 | The Four Fundamental Forces of Nature | 11.5 |
| 30 | Brain Plasticity | 11.3 |