In the past year we have had two instances where parents have dropped their kid off at the CPS office and refused to allow the kid back in the home. CPS has placed her in foster care for now.
Does that conduct violate any penal or family code sanction on a parent who refuses to care for her child?

Closest you are going to have is 22.041 TPC.

When they do it with a juvi that has a pending charge/probation we take the kid in and schedule a child support hearing and when they find out that placement costs range from $85.00 to 215.00 A DAY, they somehow find it in their hearts to take the kid back in.