There is no doubt, a few bright, fresh house plants can lift your room and your mood for very little money.
Whether you go for the sophisticated silver tones of succulents or the zingy green colour of ferns to brighten a dull corner, the most important thing is to put the right plant in the right place or you will end up with sad, frazzled and ultimately dying foliage...
I have found that trial and error is the only way to work this out. After a few weeks, if your plant looks happy in the place you have put it, leave it alone. If not, try a different room or even just a different part of the room. Most plants will not appreciate being in full direct sun such as a (north facing window) here in New Zealand: they simply fry. Read the plant label and if they prefer sun, put them near a window but not in direct sun.
Moisture loving plants often like being in the damper environment of a bathroom and try a little cactus for you kids rooms as they don't like being watered too much so you can afford to forget about them.
If your plant looks sad, don't be afraid to cut the dying leaves off and give it a seaweed feed when you water it. You will have nothing to loose and often this revitalises a dry plant enough for it to thrive again.
Every few months I like to put mine outside on a rainy, warm, still day. This not only waters them but the rain dusts the leaves for you and they will love you for it.