Hi Brian,
A long time ago, high school shop is where many of my own shop skills were developed, and they were great times, so I think that it's really super that you are building a sea kayak. You have a beautiful boat, and have done a great job.

Since you haven't ever sat in a kayak, here are a few thoughts about kayaking and building: you have probably already thought about this, but the outfitting is very important, and there are many threads here and ideas on the subject. A well thought out, comfortable cockpit will serve you well to learn paddling skills.

Either build or buy for yourself a nice paddle, and become familiar with the concept of feathering -- the degree of angle to which the paddle blades are oriented. Paddle technology and design is an extensive subject.

If you can, take a class and learn to roll your boat. Many of our sea kayaks are actually easier to roll that the modern white water boats. The when you hit the water after some practice, 3 foot waves, wind chop and currents will be your playground, and you won't be so concerned with a dunking.

I'll bet your boat will really dance on the waves.

Chris