Afraid of nesting box?

[twinmom+1VT]

Hi everyone. My girls are about just over 16 weeks now and I know we're nearing the time when they might start laying. The problem is, I don't think they like their nesting boxes. I tried putting my GC and BR in them just so they would know where they are but they get spooked and immediately jump out. The boxes are 12x12x12 with a 3" lip at the front. There's also a small bar about 1" from the front of the boxes so the girls can hop up onto that and then into the coop. I will try to take some photos and post them on here.
Any advice on how to make the nesting boxes more welcoming or will they just figure it out when they need to?

 

[Hollywood Chickens]

You can put a dummy egg or golf ball in the nesting box so that they lay in the there. they have no interest right now in the nesting boxes, but when they start laying they will go into the smallest place that they can fit into.

Right now my 13 week old chicks like to all sleep one nesting box (piled up like stuffed animals!) and the hens won't go near it