My older two boys share a room and sleep in bunk beds. Since we moved them to bunk beds it's been great as it has opened up a ton of space in their room for quiet time away from the chaos of the rest of the house. I love bunk beds.
An alternative to chlorine pools, the BioTop Natural Pools use plants to keep water clean and clear. Wikipedia has some more info on natural swimming pools as well. These could make a great addition to a permaculture design site.