Can fully understand your concern with kiddies , I have raised 4 kids in the bush myself and have had encounters with snakes whilst they were young ...I realise toddlers dont have the ability to understand danger but toddlers arent normally left unattended in the yard by themselves .With your older children ,educate them that if they see a snake in the yard to stand very still and call for dad or mum to come and help .Walk up slowly while talking calmly to your child telling them to stand very still ,get in front of your child ,and tell them to walk very slowly back listening to you at all times ,as for you, watch the snake and move very slowly or stand there till snake moves on, depending on how close you are to it or what type your dealing with .
MOVEMENT is what will set a snake off ,this is what you need to try and avoid .(this will work even with our most venomous ) just sometimes gotta have the balls to stand still :lol
you can scream like a banshee if that helps... snake wont hear ya
)