内容简介：
Key features: - Text correlated to the middle school science curriculum and developed in consultation with a science curriculum consultant- Clear explanations of key energy concepts- Descriptions of cutting-edge developments in energy production- Discussions of how each energy source affects global warming- A wealth of diagrams that enhance understanding- A glossary of scientific termsSpecial Features: - Primary Sources- Diagrams and Charts- Full-color, labeled photographs- Glossary and Index- Sources of further information