Emirates charges around 150 AED (about 40 USD) per flight leg for the Unaccompanied Minor service for kids aged 5 to 11 who must use it. For children aged 12 to 15, the service is optional and costs roughly the same if parents choose to request it.
This fee covers special assistance at the airport, priority boarding, care by cabin crew during the flight, and escorting the child on arrival to the designated guardian.
You must book the service at least 12 hours before the flight. The fee is usually paid when you arrange the service through Emirates customer service or at the airport.
Keep in mind the fee is non-refundable within 24 hours of departure and that an extra baggage allowance of 10 kg is included for the child.