I know exactly what you are going through...and padlocks are the best thing. Also, engaging the kids...like "help me clean the coop, the drinkers, the run" and "do you have any ideas about how to keep the birds safe from raccoons?" I've found getting kids involved in the safe keeping, feeding and tending animals does wonders-it builds their confidence and most important...if they feel they're involved with you and the chickens they'll probably become more protective of them. Set some boundaries..."please come to the door and tell me you'd like to help with the chickens" or something like that, if they feel part of the flock they'll probably never harm them. Educate the kids, let the gather eggs and take them home sometime, make them part of your thing and they'll love it. I hope! Good luck!