Those are certainly cute! You probably already know this, but make sure your temp is correct. They look kind of chilly in that second pic eventhough they aren't piling on top of each other.
Have they grown attached to their teddy bear? Ours didn't We tried putting stuffed animal in with our chicks so that they could have a mother hen figure, but they really just pooped all over the toy and ignored it.
Edited to include something besides the quoted text
I used a feather duster tied to the top of the brooder with the feathers just clearing the shavings. I had two chicks of the 7 that just loved it and would hide under there to sleep. The rest pretty much ignored it.