There are boat schools around the country. A sampling is listed below. And don’t forget that your local U.S. Power Squadrons or U.S. Coast Guard Auxiliary flotilla can be a great resource for safe boat-handling instruction.
Florida Sailing & Cruising School at Southwest Florida Yachts
Fort Myers, Florida
U.S. Powerboating based in Portsmouth, Rhode Island
This organization offers a variety of boat-handling courses at locations nationwide.
Shore Boating School
This New Jersey-based school offers a variety of boat-handling, safety and navigation courses.