I'm confused
I've learned so much from the wise folks who post here while reading for the past year or so.  This is the longest thread I've seen yet.  I am intrigued. 
So far I gather these facts:
--You have about 2/3 of a 1920's standard model Old Town canoe.  
--It is in unusually poor shape, lacking gunwales, seats, thwarts, and an entire stern.  Inwales are shot.  Canvas is shot.  Lots of cracked ribs.
--You need to reconstruct the missing third or it will not handle well; also, it will look like the dog's breakfast, as now.
--You are unlikely to get money from the troop for materials, which are costly: ribs, planking, gunwales, inwales, varnish, canvas, filler, paint, seats, tacks, etc. Hundreds of dollars at least.
--Ditto for tools. 
--You will need to train unskilled scouts to do the labor. 
--These scouts, like most their age, are not known for patience and capability for painstaking care.
--Their parents do not want them using sharp tools. 
Why is this going to work? 
How aobut buying a canoe that needs far less work, say, canvas, refinishing, and minor woodworking repairs, for a few hundred bucks and starting a project that is more reasonable in scope?  The funds needed would be less in the end, the work woudn't take forever, and you'd have something nice afterwards. 
I have a canoe similar in age to yours.  I love canoeing.  I was a scout.  My son is a scout.   I used to live in Padanaram.   I did not post any humorous pictures.  Stay calm.