More ideas from Ania
Ana White's loft bed storage steps.  Combine with her hack of the IKEA Kura bed (instead of ladder)

diy plans to build playhouse loft bed stairs that open to storage underneath- this would be cool as a play house outside though! toy storage outside IN the toy house! extend swings off one side and a slide off the back.

Stairs to Kura Bed

Ikea Kura loft with Trofast storage shelf as steps (not sure if I like this or not, makes the bottom bunk pretty dark, but still clever. Might have to do some rearranging and see if they like it.