Benchmark 4E
The Physical Setting: Energy Transformations
Grades 3-5, page 84

Things that give off light often also give off heat. Heat is produced by mechanical and electrical machines, and any time one thing rubs against something else.
 

NSES Content Standard B 
Physical Science: Light, heat, electricity, and magnetism 
Grades K-4, page 127 
Heat can be produced in many ways such as burning, rubbing, and mixing one substance with another. Heat can move from one object to another by conduction. 

NSES Content Standard B 
Physical Science: Light, heat, electricity, and magnetism 
Grades K-4, page 127 
Electricity in circuits can produce light, heat, sound, and magnetic effects. Electrical circuits require a complete loop through which an electrical current can pass.