Gotta Intro the Washingtonian

So I live in tiny little Roy, Washington and am entirely new to having chickens. I have two small children and I want to have a semi-sustaining home where I can grow my own veg/fruit and supply my own milk and eggs. I am not sure if I will be keeping chickens for dinner purposes or not yet... I have completed gathering the supplies to build my run and coop outdoors so decided it was time to get the chickens. I finally went with buying chicks to raise mainly because of my children. I want them to be a part of raising the chicks into laying hens so they will be entirely comfortable with handling the chickens and going out to retrieve the eggs eventually. I bought two chicks being sold as Buff Orpington and two being sold as Araucana. The Feed store told me they were between two and three weeks old. I have no idea how to age a chick so I am going with that... So far I have had them for one night and one whole day. They have been exactly as I expected. They sleep,cheep, and poo. I am currently searching for information on how old a chick needs to be before it can be taken outside. I am also curious about the difference between a rumpless and non-rumpless chicken.