Three of the Hawaiian Islands offer Jet Skis: Oahu, Big Island and Maui. Of the three only Maui has an actual season they are allowed to operate. The season runs from May 16th to December 14. This of course has to do with the annual migration of Humpback Whales coming to Maui. Although the area permitted to jet ski is limited to the size of perhaps a few acres the high pitch whine of the motors are believed to negatively impact the whales and so they are not allowed to operate during those times.
These tours are super fun for one or two people. You can have it all to yourself or if your are willing to share all the fun you can include a rider as well. Keep in mind that you can switch positions between driver and passenger at any time as well. Because this is primarily a summer event on Maui it always draws the attention of teenagers who want to participate. Minimum age is 15 years old.