I'm new to BYC but I've been lurking for a bit while I tried to convince my husband to let me have 3 or 4 "urban hens" in a chicken tractor on our 1/3 acre lot. Now he's on board, and my dad's building this tractor for me for Christmas (see http://cgi.ebay.com/ws/eBayISAPI.dll?viewItem&item=160289056937 ; we'll use hardware cloth, make the coop part a bit bigger and put on a door to lock them in at night, safe from the urban raccoons). Here's the question: this chicken project is really my baby, but I also want to get my 6-year-old dd involved as a homeschooling project. We plan to get chickens in the spring, but I'm wondering if we should start with chicks or adults (we want Buff Orpingtons). I like the idea of getting chicks and socializing them well so they won't be too skittish. My kids would love it too. However, I've heard the mortality rate can be high. Is this true? How many chicks would I need to buy to ensure I'd end up with 3 or 4 healthy adults? I do have a nice warm laundry room I could use as a chick nursery, and I have a fair amount of animal experience, although I'm new to chickens. What do you experts think?