What is kuna in school?

Excuse me, could you please clarify what you mean by "kuna in school"? Is this a reference to a specific currency or term used in an educational setting? If you're referring to a monetary unit, kuna is the official currency of Croatia. However, if this term is used in a school context, it might have a different meaning or application. Could you provide more context or elaborate on your question? It would help me give a more accurate and relevant answer.