From the DLNR DOBOR website: Effective November 10, 2014, all individuals who operate a motorized vessel in Hawaii’s State waters must have taken a state-approved boating safety course and show proof of certification upon demand by law enforcement. The text of this Mandatory Boater Education Rule is contained in Hawaii Administrative Rule Section 13-244-15.5 (available here).
The National Association of State Boating Law Administrators (NASBLA) is the organization that with representatives from Hawaii DLNR DOBOR has put together a list of Hawaii state approved boating safety courses. These courses are 80% core content and 20% state specific and are valid and reciprocal in every state like a drivers license. You only need to take the course and obtain the boater safety card once and it’s good for life. NASBLA and the state of Hawaii wants to make sure that you know about life jackets, fire extinguishers, rules of the road, buoys and in the state of Hawaii, rules about approaching protected wildlife. You should know that personal watercraft (jetskis) have special restrictions in Hawaii too. The easiest way to meet the requirement is to take one of the available online classes:
ACEBOATER.com
Boat-ed.com
BOATERexam.com
BoatTests101.com
BoatUS.org (free)
There are in class options too. The USCG Auxiliary and Windward Community College also conduct boater safety courses in a classroom format that meet the NASBLA requirements. Windward Community College is also the only place that offers the mandatory training and certification for personal watercraft (jet skis / thrill craft) and for tow in surfing.
If you have your Merchant Mariner Credential (USCG Captains license) this is accepted in lieu of the NASBLA boater safety education requirement. Just like when driving a car, boaters must have a copy of their boater education card or USCG Captains license with them while operating a boat in Hawaii.