I just couldn't make the side by side bathroom/bedroom idea work out in my head. But I felt like pulling the bathroom forward might have better results. So here is take two, slightly larger in scale. I've added the bathtub and an incinerating toilet. Man are they space hogs.
Notice the bunk beds. That automatically will put a limit on these plans. I have a boy and a girl and although some families can make room sharing work, at the preteen age I have strong feelings about separation of the genders. It's an awkward time and the last thing you need is your sibling in your personal space.
I did have a nifty idea about deconstructing our daughter's crib and fitting it in so that the bunks are more like cages.. "No," you say? Well alright, I won't kennel the kids. but it seemed like the safest way to go. ;) The last plan is drawn even larger, but it's clear to me I'm going to need some different paper. The scale of this is all wrong and too teeny tiny.