Across
- 3. compound of hydrogen and oxygen
- 6. harmful substances
- 7. standard-based sequence of planned experience
- 8. variability of life on earth
- 10. all living and non-living things
- 11. creating functional things from old unused
Down
- 1. unwanted or unusable materials
- 2. not environmentally hazardous
- 4. ability to understand ecological systems.
- 5. the ability to do work.
- 9. converting waste into useful new things