I have never put in a dust bath, mine dust bathe in dirt. They decide where in the dirt that will be. Before they were domesticated thousands of years ago they took dust baths in dirt.They don't have a dust bath, we tried but one chicken kept eating the sand
Give them access to dirt. If they want a dust bath they will manage. If they don't have access to dirt it might be a challenge.How do you create a dust bath area?
I don't know how big that run is for 8 chickens. Or how old they are. Or how big that coop is. Or what that "mad" looks like. What kind of behavior are you calling "mad"?I have 8 chickens, who are pretty bored and mad for most of the day.
Several times on here I've seen people describe their coop or run as big or something like that. They really weren't big for the flock they had. To me one of the best boredom busters is lots of room. Lack of room leads to bad behaviors.
I don't know where you are located or what kind of weather you may be experiencing. In really hot weather mine like to hang out in shade. In truly cold weather mine do not like a cold wind hitting them. By cold weather I mean close to freezing or below. I don't know your conditions or what you have to work with.
Some people put a grazing frame in the run.
https://www.thegardencoop.com/blog/2012/02/07/grazing-frames-backyard-chickens/
If you put a compost pile in the run they will greatly enjoy turning it for you with their scratching. They really love the creepy crawlies and other bits of food they find.
Many chickens love to perch. Things they can perch on adds to the quality of what room you have. Having a bit of clutter, things they can hide under, behind, or over can also improve the quality of your room.
Chickens also do a lot of resting. They may eat until their crop is filled then just go lay down somewhere, usually in the shade or under some cover, until it is digested, then they go get more. Just because they are inactive does not mean they are bored. That's kind of why I'm interested in what your "mad" looks like. It may be something besides boredom.