Use 'too cool for school' in casual conversations, not in formal settings.

Informal Slang

Sometimes said jokingly to tease someone who acts superior or aloof.

Mockery or Teasing

It can imply negative judgment towards someone's attitude or behavior.

When used in this way, it gives a compliment about someone's appearance.

Often associated with youth fashion and behavior.

Remember it's figurative; it doesn't mean someone is actually too cool for education.