Re: First small sail boat for children
As above I'd recommend one of the common one-class designs - sails and hardware will be MUCH easier & cheaper to get, particularly if you pick up some used gear to get them going and move on to new stuff if they decide to start racing. One-off or unusual designs are a huge hassle to try to race, as handicapping is difficult and racers often 'punished' for showing up in odd or highly-modified designs.
"The enemies of reason have a certain blind look."
Doctor Jacquin to Lieutenant D'Hubert, in Ridley Scott's first major film _The Duellists_.