How old are the chicks? We put a very low roost in the brooder and they love playing on that. Jumping on and off and crawling under it.
Mine are almost 4 weeks now and I have been putting in a clump of grass ( with the dirt attached at the bottom) for them to peck at.
I also throw a handful of scratch in the brooder in the morning for them to dig around at.
seconding the roost though it definitely is age dependant as to whether they will have the motor skills and balance for it or not,mine will be a week old tomorow and they still havent perfected a roost whilst its lying down yet,worth giving a try whilst its flat and letting them get used to it first.
also do the scratch thing-originaly it was just one doing it now they are all going bonkers and chucking each other out to look for treasure [of the crumble variety]

,have used a small low tuppaware type box for it-something will find in most homes probably?
a clean warm and stable [as in,one that wont fall] teddy bear with no loose bits,mine love to squash under the legs of it like they woud with a grown hen.
a small/medium rectangle/square tuppaware type container laid on its side,its not necesarily a toy but they like squashing up and huddling together in it,scratch can be put in it to encourage them to look and forage.
some non toxic marbles with nice colours/shiny patterns in them,it is more a visual toy than anything but one of mine does sometimes kick them backwards.
stick some small [ie,around credit card size] unbreakable mirrors in the brooder,or hang them in if they are lightweight, as chicks think its another chick looking back at them,am keeping mine in a chicube for a brooder which has shiny walls and acts almost like a mirror and they seem to be kept amused by their extra friends.
dont use food other than their complete crumble/mash as toys yet,a lot of sites give out food as a good chick toy when they really shoud state its for the ones who have grown up and have access to enough grit for digestion.
however,when they have grown and are outside,a good treat for them is a deseeded apple hanging from either a bought holder or home made one,we use home made for henny- staff take the middle bit out first and tie a string around it so it dangles-and henny goes completely bonkers,it keeps her lovely chicken mind entertained and gives us a laugh watching.
