Before you write in stone that the mast has to be aluminum…windsurfing masts should be looked into more thoroughly. No performance oriented windsurfing masts that I know of are made of aluminum any more…(that should tell you something) haven’t been for at least a decade…they are all a combination of Glass/Carbon, Glass/Kevlar/Carbon or Carbon alone. Most are two pieces with a very strong furrow joint. I believe they should be strongly considered for the following reasons.
1) Thoroughly tested and refined designs. Already optimized for taper, bend characteristics, weight, and strength.
2) Readily available in two pieces
3) Very Strong “Wave” style mast built to survive wipeouts in huge surf (15’+) allowing it to hold up to the on the water abuse it would see on a “kids” boat.
4) Extremely light weight for easily handling by the kids allowing them to set up their own boats.
5) World wide availability. Many areas have local suppliers. Can be ordered over the internet/phone/mail and delivered to your door for very modest shipping costs.
6) Many available on used market to further reduce cost.

While Aluminum sectioned mast could be an option for sailors which desire to do so, to ignore or outlaw a readily available glass/carbon windsurfing masts would be a great disservice. If it is truly the intent to make building and outfitting this boat easy one of the most logical paths leads straight to the windsurfing masts.

Regards,
Bob