Definately keep them in their coop and run area for at least three weeks. I let mine out in the evenings when I come home from work around 4:30 everyday. They get about 3 hours of daylight to range. While they're ranging, I like to go out and treat them occasionally so that they'll all come running when they see me. They LOVE wheat bread and rolled oats..or BOSS (black oil sunflower seeds)...scraps from whatever I'm cooking for dinner like tomato tops or vege peelings. I have one pen of chickens that I close the door while they range because there are a couple of young bantems in with them that aren't ready to range. These are completely ready when I go back out at dusk to go back in their pen. I open the door and in they go. LOL and if one of them balks at going in, I just open the door back up and send my roo Uno after her. He'll go round her up for me.
Another pen, has a flock of 5 young pullets. These can be brats and refuse to go in. They're doing better these days though, and if I toss some scratch into the run, they'll usually go in. If they don't, I go back in the house and wait til it's almost black dark..right before so I can still see, and they're usually in and on their roost by then. Short of a big bass net, you can't get a chicken to go in if it doesn't want to. The best thing you can do is to just relax. They'll go in to bed when they're ready. The key though is that initial lockin. They have to be imprinted on their sleeping quarters.