I suggest not baking anything. When the last of the sugar and flour was gone, I didn't buy any more. It's REALLY cut down on the amount of baking that goes on here, and if there is any, it's with almond/coconut flour, maple syrup, butter.
I also recommend not mentioning "Bee Wilder" in every interaction with them....it may be a fabulous program, but if you push something like that too hard, it just feels evangelical. Same is true of pushing "Primal" or anything else.
The printed Primal Blueprint Cookbook is great. The recipes in there are mostly very simple and VERY tasty.
One final thought...except for your 14 year old, your kids are really adults now. Your influence over them has waned to where it may simply be too late to do much to change their course. They'll have to pave their own way forward. I suspect all you can do is provide an example and limit the availability of the junk food (though if the kids can drive and have some money of their own, even that might not make much of a difference)
Zone diet on and off for several years....worked, but too much focus on exact meal composition
Primal since July 2010...skinniest I've ever been and the least stressed about food