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.

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.