So did you ever get the kids some handle time with the Cox planes? FYI - you can make a simple sheet balsa profile 1/2A for about 10 bucks. 24-30 inch X 3" wide wing from 3/16" sheet sanded to an airfoil. fuselage about 15-18" long with 1/8" tail surfaces. Dick Sarpolus has published about a dozen 1/2a planes like these in Flying Models over the past 10 years. You can also grab a Coroplast election campaign sign and cut it up to make a trainer. Either one will fly better and bounce back quicker than the Cox plastic. If you wanted and the Cox are in decent shape, put them on E-bay and take the cash from that to buy a .15 size trainer.