Paint the walls in a kid-friendly light color such as a soft shade of yellow, blue or green. Pick either a single hue or a variety of compatible colors to increase the open feeling of the space. If some of your chosen shades are slightly darker than others, paint the baseboards and other ground-hugging room features with the darkest color and progressively switch to lighter colors until you reach the ceiling, which should feature the lightest paint color.
Add furniture to the space as needed, but focus on ensuring a unit serves double-duty in the room. For example, instead of choosing a freestanding bench for sitting, opt for a bench with built-in storage under the seat.
Provide a storage solution for all of the toys, books and art supplies typically housed within the play space. Clutter makes a room look and feel smaller because floor space is obscured. Storage containers in light colors and child-safe shelving solutions, such as floor-hugging cubbies, help relieve messiness without overwhelming a space.
Place a mirror in a strategic location, such as across from a window or an artificial source of light. Light tricks the eye into believing an area is bigger. A mirror helps add to the effect by reflecting the light.
Pick a bed in the smallest possible size based on the child's age and the available space. A single bed should suit most school-age kids and consumes a minimal amount of floor space within a room.
Opt for a bed with built-in under-bed storage to minimize the need for additional pieces of furniture. Alternatively, incorporate containers that fit under the kid's bed into the storage solutions chosen for toys, books and clothing.
Add shelving units and storage containers to the closet, if one is available, in the bedroom. Since kid's clothes require less vertical hanging space than adult clothing, two levels of clothes can be stored in the closet. This may eradicate the need for a dresser altogether or, at least, reduce the size of the unit needed.