Do you eat school lunch every day in the cafeteria? Or do you sometimes pack a homemade lunch from home? If you pack your lunch every once in a while, chances are you use resealable plastic bags.

Resealable plastic bags — sometimes called by a brand name, such as Ziploc® — are those little clear plastic bags you use to keep your sandwiches and chips fresh. They usually have some sort of sealing mechanism, like a plastic zipper, that allows you to seal the bag to keep out air.

Keeping air away from foods allows them to stay fresh longer. Bacteria and other organisms in the air will break down food items over time if allowed to come into contact with them. Sealed plastic bags keep these organisms from getting to your food.

Resealable plastic bags can be used for more than just transporting sandwiches, chips and snacks to school for lunch. They’re also used to keep leftovers fresh in the refrigerator. Many people also use them to store food in the freezer for use in the future.

The history of the resealable plastic bag starts out in 1951 at a company named Flexigrip, Inc. Flexigrip developed a plastic zipper from patents it bought from inventor Borge Madsen. These zippers were originally used as parts of binders and briefcases.

Over time, however, plastic zipper bags were developed. Eventually, in 1968, Dow Chemical Company began to market its Ziploc® brand of resealable plastic bags to grocery stores. They turned out to be very popular.

Today, these types of bags are available in many different sizes and styles, from snack and sandwich bags to craft and freezer bags. You can also buy bags with expandable bottoms that stand on their own. Some bags even allow you to steam food in the microwave!

Resealable plastic bags can be used for so much more than just storing food, though. Here are a few other common uses for these handy bags:

  • Jewelry: Many people use resealable plastic bags to store small pieces of jewelry, including beads.
  • Office supplies: Want to keep track of tacks and paper clips easily? Store them in convenient resealable bags!
  • Games: Always losing the cards or dice from your games? Keep these items together in a resealable plastic bag and you’ll never be searching for those missing pieces again.

Today, many people try to use less plastic because of its effect on the environment. Manufacturers of resealable plastic bags have taken steps to become more environmentally-friendly. For example, Ziploc Evolve bags contain 35% less plastic and are made using wind power. They’re also packaged in recycled paperboard.

36 Join the Discussion

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    • That’s great, Wondergirl101! We can’t wait to have lunch after reading this Wonder! Thanks for sharing your super guess for tomorrow, too! :)

    • We’re so glad to hear that, Hannah! Packing your lunch is a great way to enjoy a homemade treat at school! We Wonder what you LOVE to eat at lunchtime? :)

  1. The video was weird, but I liked it! I did not know that putting pencils in a bag full of water without it dripping was possible. Great wonder! Thanks! :)

    • We couldn’t believe it was possible until we saw it, Berkleigh! We Wonder if you have ever conducted a science experiment that totally shocked you? We are so happy you’re WONDERing with us today! We’ll see you soon! :)

    • We think it’s a great way to transport your food or small belongings from one place to the next, Marsha! However, there are also reusable containers to keep your food fresh, too! It’s another way to reduce waste and promote recycling! Thanks for WONDERing with us today! :)

  2. I liked today’s wonder I pack a lunch when I’m going to school or when I’m going on a picnic I think tomorrow’s going to be about bees.

    • That’s great that you pack a lunch on your own, Kamron! What a great way to eat a healthy, homemade lunch while you’re at school or away from home! Sounds like your guess for tomorrow’s Wonder is buzzinggggg along, too! :)

  3. Lots of times I don’t really pack my lunch but I may have to start because I know what their serving in school lunches and it’s not making kids stronger, healthier, or even able to believe that they can do anything. For example in dance girls and or boys don’t think that they can make it to the top and do a scorpion!
    Sincerely Danielle :)

    • We think packing your lunch is one great way to choose healthy food options, Danielle! Some Wonder Friends attend schools with great cafeteria choices, and others… not so much. We are glad that you remembered that eating healthy foods will fuel you for the day, and help you accomplish great things, too! Nice work, Danielle! :)

  4. We learned about advertisements in school and this sounds like an advertisement for plastic bags. Also our school encourages us to bring our lunches and snacks in reusable containers.

    • WOW, that’s awesome, AZ! WONDERing about advertisements is a cool place to start– and you’re right, the Wonder video does remind us of an ad! We think that your school is very environmentally conscious, too! We think that reusable and recyclable containers are a great place to start when it comes to helping the Earth! :)

  5. I knew some facts about packing lunch, but I didn’t know that the zipper kept your meals fresh and keeps the air out.

    • Great to have you WONDERing with us today, Emelien3356! It sounds like you were able to learn something new from this Wonder. We think that is WONDERful! Keep WONDERing! :-)

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Have you ever wondered…

  • Do you pack your lunch?
  • When were resealable plastic bags invented?
  • What are some other uses for resealable plastic bags?

Wonder Gallery

Zip Lock BagmickeymooVimeo Video

Try It Out

Ready for some crafty and tasty fun? Resealable plastic bags aren’t just for storing food. You can use them to make food, too. They also come in handy for crafts. Here are some fun ideas you and your friends and family can try at home:

Do you have another great idea for a fun craft to make with resealable plastic bags? Share it with your Wonder Friends by posting it to Facebook. We can’t wait to read your ideas!

Still Wondering

Visit Smithsonian’s History Explorer to learn how Aladdin Industries profited from the success of The Jetsons television cartoon series in the fall of 1963 by introducing a Jetsons Lunch Box featuring that space-traveling suburban family and their robotic maid.

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