Awesome Loft Beds--Since you won't have a window on the one end of your upstairs, this could be a fun idea for the kids area. Not necessarily a bed, but a 'loft' on top of a 'hide-out' area---or something. The bookshelf stairs are a neat idea too.
Little girls' room? I want this for myself! As if the bed nook wasn’t cool enough, that door leads to the closet, which holds a ladder to a reading space, with the “balcony” window above the bed to look out!" Ultimate little girls' room!
Tent on top bunk . Source: Delightful Distractions - HOME SWEET HOME. Easy DIY using fabric or even sheets. For bottom, build in rod and use curtain hangers or tack Velcro to wood and panel for a more stationary curtain. For top bunk, hang from ceiling.