I would have suggested that experience with the joining method that's offered be had before the class. Some disagree with this but it's my opinion. Any of the basic tube sets out their are fine, albeit with 'thicker" walls for the first few frames to minimize the boo boos and results of aggressive filing. My flavor is the Verus tubes from True Temper (might as well support our guys).

I suggest that you build a bike that you'll be able to use routinely.

As you go forward remember that when you build for another you are "selling" your skills and acquiring liability. To be ethically fair you should have insurance before this step. Andy.