In picking designs for a class, I very often have to take into account the lowest common denominator - in this case, the inexperienced paddler and woodworker. The difficulty here is to pick something that satisfies everyone - a truly difficult task. I want a design which is safe to use, easy to build, but broadly aesthetically pleasing.
So for my current class, I've picked three distinct designs for my students to build. I think that's pretty generous, all-in-all. For the instructor, to have students building 8 different boats in some unknown combination of these three different designs is a challenge.
S. Jeff Horton's Stonefly Canoe :
Dave Gentry's Chuckanut 12 kayak :
Dave's slightly larger Chuckanut 15 tandem kayak :
When presented with these options, students will sometime say that they want to design their own boat. Unless you're a naval architect on the side, I tend to discourage this.
Take for example this little beauty found on Craigslist which I think is a better than average version of a builder-designed boat:
It made me wonder if the design inspiration came from the '80's classic video game Asteroids:
That's not to say that every beginner is going to design an awful boat, but that's the way things tend to go. It takes experience to design a good-looking boat that's structurally sound and behaves well functionally for the paddler in terms of speed, stability and tracking and turning abilities that's light in weight. It also takes somewhat of an artist's eye to make an appealing design as well.
I'll also get students who decide that they're going to alter an existing design in some significant way - length, width, depths, overall shape, etc. without ever having paddled the boat in question as it was designed. Very often this can have unexpected results and I generally tend to discourage doing this as I want the student to complete a boat that looks and functions nicely.
I'll also have students who decide they want to sign up for a particular class - in this case, a non-traditional skin-on-frame boat-building class where we use plywood frames with long wood stringers between the frames. They will then ask if they can build a traditional skin-on-frame boat with steam bent ribs. Some will go totally off-book and want to build a caravel or lapstrake boat. Sorry, not in this class - perhaps in a future class offering, but we're building non-traditional skin-on-frame boats right now. If you want to build a skin-on-frame boat, I think you'd have a great time in my class, but building by another method is just too much of a distraction for the instructor and the rest of the class.
Some will also ask if we can convert an existing design for another build method to the one that the class is offering, which is generally possible, but takes some serious time and effort to prepare on the part of both the instructor and the student - along with being an untested build.
Lastly, we'll have students who decided to look a little further afield for a design being offered in the same build method, but that we don't currently have plans for. This is a little bit more do-able as most of these designs have at least been prototyped by their designer and built by other builders - takes some of the pressure off of whether the student can build a successful boat. It takes a little bit more work on the part of the instructor to get up to speed with the intricacies of that particular design, but usually isn't a disaster. For example, I had an experienced cabinetmaker build a beautiful cedar strip kayak in a cedar strip canoe building class without it being a disaster.
So, if you come to sign up for my class and see me cringing slightly when asking me if you can make changes to what is being offered in the class in terms of methods and designs, now you know why!