Dude - put her on the tiller and be done with it! You'll be suprised how much better you will perform in this arrangement. There are countless examples of the success of this strategy.

You want to get kids in the sport - 3 easy steps:

1 - don't be "Coach". Grab the camera and become the photographer. Shut your pie-hole and let the kids figure out how fun sailing is for themselves. By "ooh-ahh" and taking pictures, you're seriously boosting their self-esteem.
2 - give the kid the tiller and say "here you go, let's sail!". Let him/her decide WHERE to go. They don't need the physics/aerodynamics discussion or a schooling on race tactics (yet)
3 - the rest of the crew should adapt to where the kid is sailing (in terms of trimming the sails)

Intervene only when they are going to put the boat on the rocks or something drastic like that. Let them keep the tiller as long or as short a time period as they like.

By the way, this works for spouses / love interests, too...