My friendliest bird is the Buff Orpington. That said, the Red Sex Links I have raised from chicks are pretty friendly too. They come running when I step out of the car or out the door. If they hear or see me, they run to me. They occasionally get out and all I have to say is get home and they start to the pen. I would say that any of those suggested that you raise from chicks will be really friendly to you. If the kids are part of the raising process, they probably will be friendly to them as well. They lay very well, probably the best egg layers I have (they were bred for egg laying). As far as a meat chicken, they aren't much for that, though. I don't know much about meat chickens.
For a coop, build what you can afford. Don't think you need a special place. Look at the suggestions on here and take from the ones you like. One suggestion I will make, however, for when you make the pen (can also apply to the coop) around the outside, make sure to lay some fencing on the ground pointing out, away from the pen. Six inches to a foot will probably be enough, err on the longer amount. Pin it down a little, as the grass grows, it will hold it down. Believe me, ever try to pick up some fencing that has laid on the ground for a few months? Anyway, this keep critters from tunneling in. I used 2x4 welded wire (we call it dog wire around here) It was a little more than the chicken wire, but it is much stronger.