Lately, in the past week, my 5 month old rabbit has been chewing on her litter box and then flipping it over, both litter boxes, the one in her cage and the one outside the cage in my kitchen.  Why is she doing this?  Is there a reason?  Will it ever stop, its to the point where every day I have to change her bedding in her cage because her cage is filled with poop from the flipped litter box.

Thanks

You might try getting a covered cat litter box.

Or finding a way that you can attach those boxes to something. The one that is in our cage hooks to the side. Oren was like that before he got fixed, more so he liked to push them around. Or she could just be goign through a bratty stage.

you could get a corner litter box that hookes up to the cage.

My Carrera did that with her corner litter box forever! Drove me crazy! She would throw it all over and never use it. After I got her fixed she was much better but I had to switch to an extra large cat litter box and she is very happy with it and never moves it.

Sounds like as she's reaching sexual maturity, she may be getting a bit destructive with things.  Some females dig, move things around to get them out of her way, or just venting pented up energy due to her hormones.

Another member mentioned clipping the box to the cage.  That works well.  You can usually get clamps from a hardware store.