Benchmark 4E
The Physical Setting: Energy Transformations
Grades 9-12, page 86
Whenever the amount of energy in one place or form diminishes, the amount in other places or forms increases by the same amount.
NSES Content Standard B 
Physical Science: Conservation of energy and the increase in disorder 
Grades 9-12, page 180 
The total energy of the universe is constant. Energy can be transferred by collisions in chemical and nuclear reactions, by light waves and other radiations, and in many other ways. However, it can never be destroyed. As these transfers occur, the matter involved becomes steadily less ordered. 

See also the general discussion in Unifying Concepts and Processes: Constancy, change, and measurement