My children go to their dad 1,3,5 weeken of the month, I dont know what is the law for spleeping areas, My children are 12 years old.

Male or female kids?

It's my understanding that they are supposed to have their own beds & sleeping area. My ex specifically got a 2 bedroom apt & bought my girls bunk beds because he knew that they needed it and, he has them they same weekends your ex does.

I think it may depend on the state, but I think in my state they children have to have their own bed, not necessarily their own room. My ex called CPS on me (out of spite) and they ended up investigating both homes the kids live in. They were okay that my ex said he was sleeping on the couch - although most nights he was sleeping in my 6 yo's dd's full size bed with her (I'm not saying there was anything going on, but my 2 boys were in the other bedroom so there wasn't a 3rd bedroom for him to be in)

Well you could always call CPS on him about it. Or Google it for your state.

they could sleep on an airbed or on the couch at the age of 12, law or no law, esp if they are girls, the should NOT be sleeping with their father,, get them an airbed for them to take.

I would invest money and get 2 twin aero beds that they can take with them when they go visit their dad. They are comfortable and worth it. They are no big deal to set up and put away. It's a lot better then sleeping with dad regardless of your kids sex.