Benchmark 4E
The Physical Setting: Energy Transformations
Grades 6-8, page 85

Most of what goes on in the universe--from exploding stars and biological growth to the operation of machines and the motion of people--involves some form of energy being transformed into another. Energy in the form of heat is almost always one of the products of an energy transformation.
 

NSES Content Standard B 
Physical Science: Transfer of energy 
Grades 5-8, page 155 
Electrical circuits provide a means of transferring electrical energy when heat, light, sound, and chemical changes are produced. 

NSES Content Standard B
Physical Science: Transfer of energy 
Grades 5-8, page 155 
In most chemical and nuclear reactions, energy is transferred into or out of a system. Heat, light, mechanical motion, or electricity might all be involved in such transfers.