| 35 × | agriculture | 33 × | getting to know plants | 31 × | physical and chemical changes | ||
| 35 × | forests | 33 × | electric current and its effects | 31 × | water: a precious resource | ||
| 34 × | some mechanical properties of matter | 33 × | motion and time | 31 × | fluid mechanics | ||
| 34 × | molecules and nuclei | 33 × | electric charges and fields | 31 × | life lines of national economy | ||
| 34 × | electromagnetic induction and alternating current | 33 × | weather | 31 × | structure of atom | ||
| 34 × | transportation in animals and plants | 32 × | comparing quantities | 31 × | heat | ||
| 34 × | wave optics | 32 × | air | 30 × | heat and thermodynamics | ||
| 34 × | environmental chemistry | 31 × | wave motion and waves on a string | 30 × | motion and measurement of distances | ||
| 33 × | simple harmonic motion | 31 × | fun with magnets | 30 × | separation of substances | ||
| 33 × | electricity and circuits | 31 × | linear programming | 30 × | nutrition in plants |
