Chickens won't go outside

[BigBen]

I have 7 RIR's they are 9 weeks old. I got them 11 days ago. I kept them inside for 7 days and then opened the poop door.
Once I was able to coax them out with food and then they all ran back in.
Today I picked up some cracked corn and spread it around and on there ramp.
They will come out onto the ramp and eat a little and then run back in.
I have grass clipping on the ground inside there run.
I was wondering if they are so used to the pine shavings inside the coop that they don't like the clipping.

 

[Dirt Road]

Give 'em time. Very soon, they will be lined up at the exit waiting for you to open it each day. Youngsters are especially nervous about anything new.

Jim

 

[BigBen]

Once again I spoke to soon.
I desided to take my ATV for a ride and when I went out side they were all in there run.