Hi there, great to hear another windsurfer is being helped into the club! good work! Both of my teenage kids windsurf, it´s a bit of a process to get them from absolute beginners into footstraps, planing, into the waves etc, but there is no better family sport once everyone is out there enjoying it!
start them off slowly, on the board with you is good, either on the front or between your legs. The second lower boom is also a good option too! an irig or a fanatic ripper rigs are perfect for kids to learn to sail by themselves too! good luck!