Good point with the foam...you probably want to use epoxy on blue foam - not polyester resin (it will melt it).

You may want to cut a lite-ply plywood profile of the boat from the line drawing side profile (get this thin plywood in hobby shops). Glue foam to either side of the ply and sand to shape. The plywood will make a good reference point to sand to on the top and bottom and then you shape the sides by hand from there.