None of the girls will use them. They go in and move the straw around, but no eggs. We've tried altering them (bigger,smaller,light,darker). We have a perch for easy access. We've put decoy eggs in there-all to no avail (they lay on the floor right in front of the darned things!
).
Can you teach a chicken to use them once they have decided not to? Any suggestions?

Can you teach a chicken to use them once they have decided not to? Any suggestions?