Kids these days spend a ton of time online, so why not encourage them to use the computer to earn a little cash?

Indeed, a recent study from the Pew Research Center shows that 24 percent of teens, ages 13 through 17, go online “almost constantly” and that 56 percent of teens reported going online at least once a day.

But if you fall into one of these age brackets, all that time spent on the tablet, smartphone, or desktop doesn’t have to be devoted to Facebook, Instagram, or Snapchat. Instead, try spending some of that screen time making money selling your old stuff at an online consignment site – with your parents’ permission and help setting up an account, of course.

Earn Your Allowance

You won’t even need a fancy camera or mannequin to make your outgrown clothes, toys and games look their best. Consignment sites like Swap.com are making it easier than ever to sell or swap online by organizing items and taking photos for sellers. All you have to do is collect a box of items they’ll accept and ship it off. Then, the site organizers will let you know they received the items and allow you to set your sales prices before they post photos – leaving you with nothing to do but wait for the extra cash to start coming.

That said, there are a few things you should consider to get your career as an online entrepreneur off to a strong start. Here are some pointers for successfully selling toys, clothes, sports gear, books, DVDs, and music online:

Tips for Selling Toys

LIVESTRONG.com recommends cleaning toys and checking online with the U.S. Consumer Product Safety Commission to make sure none of the toys you’re thinking about selling have been recalled.

Next, separate toys that are in excellent condition from those that might be missing parts. Toys that are a little more worn or are missing a piece or two can be donated or maybe even sold in batches or at a discount at your neighborhood’s next old-fashioned garage sale. Then, take a look at the nicer stuff and consider online consignment sites for educational toys, action figures, classic board games, model cars, and popular brands such as Star Wars, which are likely to make you the most money.

After all, when was the last time you took that Millennium Falcon out for a spin?

Tips for Selling Clothes

If you’ve got more clothes than toys lying around, your first step should be to make sure they’re clean and in good condition. Also, consider bundling several similar lower-cost items like T-shirts or tank tops together in a single-price package.

Further advice from Glamour recommends thinking like a department store manager when it comes to timing your online sales. Winter coats are probably not going to be a hot item in August, but will likely attract attention in September or October. At the same time, you might want to send off that old prom dress as early as January or February when teens start thinking ahead to the big event.

Glamour also encourages sellers to be realistic about prices. You may have saved up $200 in birthday and Christmas cash to buy that perfect prom dress, but it isn’t likely you’ll get that $200 back when you resell it. The standard at yard sales calls for pricing items at 20 to 30 percent of what they would cost new, according to the Los Angeles Daily News, though you might be able to ask for more depending on the item and its condition. Smart sellers research similar used items online and use those list prices as a guide.

Tips for Selling Sports Gear

Used sporting goods can be a hot seller at consignment sites, according to Consumer Reports. You can make your gear look good by cleaning equipment as you go, letting it air out, and storing it properly while it’s in use. Refill and scrub deflated balls. Try to clean leather goods, such as baseball gloves, with a dry brush or a sponge soaked with just a little water before letting them dry and treating them with leather conditioner.

Remember, also, that practice uniforms don’t have to be perfect to sell, since parents often like to buy extras and don’t mind a few little flaws, according to advice from the Consignment Mommies blog. Ask a parent for tips on pre-treating and washing used uniforms to help them look their best. Odds are, they’ll be thrilled that you’re not only cleaning out your closet, but also learning the finer points of laundry duty.

Tips for Selling DVDs, Music and Books

It’s easy to see if books, DVDs, and CDs are in good enough condition to sell. Putting in a little effort with some disc cleaner and a soft cloth can work wonders. So why not bundle those Harry Potter books, or the Twilight saga, and sell them to someone else who hasn’t read them 10 times yet? If watching “Mulan” now and again is still a guilty pleasure, don’t forget that you that can always cue it up on Netflix.

Getting More than Money

Selling stuff, rather than tossing it, isn’t just good for your pocketbook – it’s good for the planet as well. Selling the stuff you’ve outgrown, or won’t use again, will not only make you a little money and help keep used goods out of the landfill, it’ll also help you be more organized. Getting rid of old toys and books will make your room neater and a snap to clean and decorate. With fewer things crowding your closet, it’s easier to see what you have and makes assembling killer outfits that much simpler.

So now, take a second to look around you. What toys and games do you have lying around your room that you could convert to cash through online consignment sites?