: Next month I plan to take a week and build a simple SOF with my small 10
: year-old, Calder.

Dang it! I wished I had saved those plans! My dad and I built two kayaks based on Mechanix Illustrated's "Canvasback Kayak" that were published in the '60's, we built in '86. Only my dad and I scaled them up to "adult" size. I have found the adult "upgrade" that MI published in the early '70's, on the web (unfortunately my dad's collection of MI's we either missed this article or he was missing that issue when we were looking for plans on how to build a kayak), but never ran across the original article on the 'net. I wished now that I could have saved it and scanned it in for those of you looking for kid sized kayaks. I want to say that the original length was 12', but its been a long time since I had seen those plans (I photocopied them for a guy back in the early '90's) and the original beam width I cannot even begin to guess.

The kayak design is similar to the Clark Craft kayak designs (recommended by another responder), therefore for most enthusiasts they are outdated. But do the kids really need the latest and greatest design kayak that they will, physcially speaking, outgrow? But that is a question that only you and the kid you are building it for can answer (i.e. if he/she is pushing the limits of kayaking, then a more advanced design would probably be worth building, vs. most kids who probably like the kayak because it floats and can be propelled relatively easy and is faster than other boats they've paddled/rowed).

Good luck whatever design you decide on,
Paul