15 Things to Throw Out ASAP in September, According to Professional Organizers

Now that school has started, sort through items you haven't used. "If you stocked up on markers, crayons, or notebooks during back-to-school sales (I totally do this), but your drawers are overflowing, consider donating extras to your local school, daycare, or YMCA," says Nichole Gehman of Organize by Designe.

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Don't blindly pack up summer toiletries before checking expiration dates. "Start with the things that will not make it another season, like sunscreen, bug spray, or aloe gel," says Laura Ellis, founder of Organized by Ellis. "Toss the sandy, half-used tubes that have seen better days."

"Toss anything bought in June with a summer plan—the craft kit, the gardening project, the half-used journal—but which never got touched over the summer," suggests Dr. Lark.

Be honest as you evaluate it all. "If it didn't get used in its intended season, it's worth asking honestly whether it will next year, or whether it's just taking up shelf space out of guilt," she says.

Donate or toss any clothing and swimsuits that didn't get worn this summer. Keep in mind that kids are likely to outgrow their summer clothes by next year, so donate any unworn or ill-fitting items. "They grow so fast," says Gehman.

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After a long summer of playing outdoors, it's a great time to organize the shed filled with sports gear. "Sporting equipment—bikes, helmets, swim goggles, cleats—should be inspected, repaired, or replaced before the fall season," says Dr. Lark.

Sports equipment in good condition can be donated to local community centers, youth programs, or thrift stores.

Take a pass through your summer books—whether you read them or not. "Now that books are a click away, they tend to pile up before we can read them," says Maeve Richmond, founder of Maeve's Method. "Send the ones you don't plan to read soon (or ever!) packing—off to a friend, colleague, or book donation organization."

Books can be donated to charities, your local library (just call first to confirm!), or other community organizations.

'Tis the season of packed lunches, so it's a great time to re-evaluate your collection of food storage containers. "Review what you own, then hang onto the ones you'll realistically use during the week—like for lunch or leftovers—and release the rest," says Richmond, who also suggests considering glass containers.

"Summer has a way of filling our homes with extras," says Lark. "Souvenir cups, freebie water bottles, promotional tote bags, and beach towels multiply quickly—pare them down." Toss any beach towels or summer gear that is damaged and donate any extras. Keep in mind: Animal shelters typically accept used beach towels as bedding.

For families with kids, schoolwork piles up quick. Before you get too overwhelmed by the new school year, "edit or archive children's art and memorable schoolwork from last year," says Zaslow. "Toss random scribbles, worksheets, and used notebooks."

Don't put damaged items into storage—you'll regret it next summer. "Say goodbye to worn-out pool floaties, cracked goggles, and broken beach toys, along with flip-flops, sandals, and swimsuits that are stretched out or never got worn," says Ellis.

With school in session, an organized pantry is key. "Go through your pantry—summer cookout condiments, stale chips, and nearly empty cereal boxes often linger longer than they should," says Lark.

Before you pack away outdoor furniture, check for damage—think faded couch cushions, tears in rattan chairs, or rust on metal tables.

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"Summer is a season for eating out," says Richmond. "Check your kitchen, cabinets, and car—you may have a pile-up of fast food extras. You know the suspects—plastic forks, napkins, salt and pepper packets, condiments, and straws."