They are geometrical forms which are said to act as a template from which all life springs. They are named after the ancient Greek philosopher Plato. To the Greeks, these solids symbolized fire, earth, air, spirit (or ether) and water.
Plants in the bedroom -- or any room -- are always a good idea! The crates on the wall also help create a little bit of extra storage, which is a great decor idea for small spaces and apartment living.