Units that consist of a desk, drawers and shelves are commonly placed in children's bedrooms to encourage them to study. However, when these units are placed up against a wall or window, children will find it hard to focus, due to various fung shui factors.
When a desk is placed against a wall, there will be no ming tang or 'bright hall' - a space that allows positive chi or energy to accumulate - above the person sitting at it.
When ming tang is lacking, a sense of tension develops. Additionally, a person sitting at a desk flush against a wall will often have their back to the door, and therefore be unable to see who enters the room, resulting in distraction and impaired concentration.
When a desk is placed facing a window, activity outside or sunlight filtering through will distract anybody sitting at it.
Ideally, a desk should be placed in such a way that the person sitting at it has support behind them and a clear view of the entrance to the room. With space constraints, this may be difficult to achieve. However, from a fung shui perspective, it is definitely worth trying to position a desk correctly, as you may discover yourself focusing on your work and achieving more as a result.