The FCC requires a Marine Radio Operator Permit to operate radiotelephone stations aboard certain vessels that sail the Great Lakes. The Marine Radio Operator Permit is also required to operate radiotelephone stations aboard vessels of more than 300 gross tons or on vessels that carry more than six passengers for hire in the open sea or any tidewater area of the United States. You're also required to have the Marine Radio Operator Permit to operate certain aviation radiotelephone stations and certain coast radiotelephone stations.

The MROP preparation class is taught by a licensed FCC Communications Expert and Radio Operator.  The course is approximately two hours in duration followed by a computer based exam issued by iNarte/Global Explorer.
 

You must also register for the exam and your FCC license at their website:  

iNARTE/Global Explorer FCC License Service