1. food webs and energy flow, predator identification, sun as energy source, food chains, impact of toxins on other species
2. chemical reaction evidence, vinegar and washing soda, identification of reactants/products, observations like bubbling and temperature rise
3. puberty changes in males and females, specific (hips widen, deeper voice), shared traits (hair growth), human development stages
4. soil moisture experiment, mass measurement at different steps, equipment setup for heating, explanation of mass loss by evaporation
5. gravity vs mass concept, correct units (kg, N), differences in gravitational force across planets, weight calculation with gravity changes
6. physical changes (boiling, evaporation), reverse process (condensation), differences in rate/location, example of other physical change