Technology changes fast.  And that means most families have electronic clutter—cellphones, cameras and calculators, laptops, tablets and e-readers, talking toys, video game systems, and media players. One website estimates that the average American household has no less than 24 electronic devices, many of them sitting unused in drawers and cupboards.

Although such items aren’t likely to sell well at a traditional garage sale, they can be a source of cash, sometimes surprising amounts of cash. The market for refurbished and rebuilt devices is strong, especially overseas, and a flourishing community of buyback websites will pay for unwanted gadgets without the hassles associated with real world garage sales.

Getting rid of electronic debris is an ideal end of summer project. Not only will you de-clutter the house but you’ll probably earn enough to defray at leastsome of the costs for new back-to-school gadgets. Enlist your kids to go through closets and play areas, gathering up any unused object that needs a battery, a charger, or a power cord.  Even items that no longer work may have value. Use a damp cloth to clean off grime and finger prints. Locate cords, accessories and, if possible, manuals and original packaging.

Then head to the websites below to see what your items are worth. (You may want to recruit an adolescent to do this research.  Just offer a percentage of the proceeds.)  Because prices vary a great deal, it’s a good idea to start at Pricenomics.com, a website which quickly surveys the web to determine a fair price range for used items in a wide range of categories.  Usell.com is also helpful. By aggregating information from a number of reliable buyback sites, it allows you to zero in on the best offer.

Buyback websites accept different items. Most provide a detailed list with menus that help you identify the precise model in your possession. (For videos and games, you may also need the ISBN number.) You, in turn, answer questions about the condition of what you have to sell. The more accurately you answer these questions, the more likely it is that you will get the full price offered by the site.

If you agree to the price, the company should pay for shipping, either by providing a mailing label or by sending a carton for larger items. Before shipping, erase personal data from computers and cellphones.  Even though some companies promise to do this for you, you don’t want to take the chance that information will wind up in the wrong hands. To find instructions, search for “wipe data” and the name of your device.

For peace of mind, make sure the website you use has a customer service phone number as well as a street address just in case you need to track down payment. Because payment procedures vary, you’ll want to keep copies of shipping labels and other paperwork. Some companies send a check; others deposit funds into a PayPal account. A few offer gift cards to Amazon, Target or other companies, and some give credit toward new merchandise.  Bestbuy.com, for example, will trade in anything they’ve ever sold for a store credit. The website you choose depends in part on what you have to sell. Here are some suggestions:

• Cellphones – Apple products, including iPhones and iPads, are in high demand at sites such as Newtonshead.com and Tunecycle.com. Swappa.com specializes in Android devices.  For cellphones of all kinds, check out Securetradein.com, Cellitused.com, or Gazelle.com. Gazelle allows you to take payment in the form of an Amazon gift card and also makes it easy to donate the value of your phone to one of their approved charities.

• Video Games – Secondspin.com offers cash for used games, CDs, and DVDs.  Spun.com gives credits that can be used toward other games. Amazon also has a trade-in site that accepts all kinds of media including books. Just type “Trade In” into the search box at the top of the page.

• Electronic Toys – Interactive toys like Leapster and Hexbugs sell reasonably well on eBay.  Checking Whatsellsbest.com will give you an idea of which items are worth listing and will help you avoid selling valuable collectibles for less than they are worth. The site also has a Toy Selling Guide with useful pointers. Those who don’t want to go through the hassle of setting up an auction can check to see whether an electronic item is eligible for eBay’s Instant Sale option (instantsale.ebay.com)

• Gadgets of all kinds – If you have a grab bag of items, you’ll do best with a site that accepts everything from camcorders to headphones.  Buybackworld.com has a good reputation for paying as promised, and they offer a fundraising option for parent clubs and other organizations. Nextworth.com has a partnership with Target that allows you take electronic items directly to a store and get a gift card on the spot. Buymytronics.com has the endorsement of the Better Business Bureau and offers to match prices from other sites. Guzu.com plants a tree for every successful transaction.

Even when they can’t offer money because your electronics are too damaged or too out of date, some of these sites will pay for you to ship items for recycling. Take them up on this offer. Electronic devices often contain toxic materials so they don’t belong in the landfill. They also don’t belong at the back of the closet or the bottom of the toy box. Someone somewhere wants your stuff and, with the help of these websites, you can enjoy the financial rewards of a garage sale without ever setting up the card table.