Soon parents everywhere will start gearing up for a new school year, going though drawers and closets to remove items their children no longer use. In some cases, parents may find that it’s not only clothes their children have outgrown, it’s their bedroom, too.

Pastels, primary colors, firetrucks and fairy princesses: all sensible choices for a baby or toddler’s room but not so cool for a teen. Unfortunately, a makeover every few years isn’t budget-friendly. Nor is it practical, says designer Annie Elliott, of Washington.

“If you’re running around with kids, you’re not going to have the energy to update their rooms,” she says.

Sound familiar? There are some simple steps for taking the design of your child’s space from toddler to teen without spending too much money.

Avoid themes

“Themes can be very, very cute, but it makes it very hard to transition later,” says Christiane Lemieux, founder and creative director of DwellStudio, a home furnishings company. “You’re going to have to eventually redo it.”

So, forget the wall-stenciled soccer balls. Make less of a design commitment by incorporating your child’s interests and hobbies with accessories.

“Have a motorcycle on the dresser or on artwork or pillows instead of on the rug or textiles,” suggests Lily Kanter, chief executive and co-founder of Serena & Lily, a baby bedding and furniture company.

Invest in furniture

Rather than buying furniture that will be tossed when your child gets older, spend now on quality pieces that will last into the teen years and beyond. Once the child has grown, well-made furniture can always be re-covered, refinished or used elsewhere.

For her son Holden’s room, Mia Worrell, of Arlington, Va., paired a wool area rug, a nice wood dresser and a custom shelving unit with an inexpensive toddler bed from Ikea, which will be replaced with a regular-size bed as soon as Holden, 2, is old enough.

Spending on shelving (even splurging on built-ins) is worth the investment, says Elliott. “They will go from diapers to toys to books to aquariums, whatever the child is into,” she says.

Choose bold paint

“Nothing makes a room look more designed than a great color, and a coat of paint is a pretty inexpensive way to do it,” says DwellStudio’s Lemieux. She suggests going bold with color as early as the nursery days.

And don’t forget about the ceiling, she says. “Putting stripes across the ceiling is really easy and will make your kid’s room look decorated in a second. It really makes a great visual impact.”

Sharing a space

Decorating a child’s bedroom should be fun, but decorating a bedroom that siblings share can be a challenge. Here are some ideas for a shared space:

• If you allow each child to choose a color for one wall, limit their choices to ensure the colors look good together.

• Allow each child a shelf that’s completely theirs to display collections. (This is also a good way to control clutter.)

• Let each child choose their bedding.

• Divide the closet so each child has a side. If the closet is small, hang two rods and have a step stool handy.

• If there isn’t enough space for separate dressers, give them separate drawers.

• Hang a canopy over each bed to create a private space.

• Consider a loft bed for an older child; it creates a room within a room below the mattress.

• Siblings are expected to co-own games, DVDs, etc., but their bedroom should be a place where they can have some things that are all their own.