Wonder Contributors

Today’s revised Wonder was inspired by a couple Wonder Friends. First, MJ from Wilmington, Delaware Wonders, “How do clouds move and make shapes?”  And, Sue of Kaycee, Wyoming Wonders, “What determines when a cloud will release rain?” Thanks for WONDERing with us MJ and Sue! 

Rain, rain, go away. Come again some other day. That’s how we feel sometimes when all we want to do is go outside and play.

However, rain plays an important role in our world. It replenishes the Earth with water and helps our plants grow. Without regular rainfall, our world would be a dry, dusty place that wouldn’t be any fun at all.

If you see clouds roll in on a sunny day, it could mean that rain is on the way. Have you ever stared at those clouds and wondered whether they hold rain and, if so, how much?

As it turns out, that question isn’t easy to answer. Why? Clouds aren’t like buckets, so they don’t really “hold” water like a bucket would.

Whether you realize it or not, the air around you is filled with water. Water comes in three forms: liquid (that you drink), solid (ice) and gas (water vapor in the air). The amount of water inside a cloud is no different than the amount of water in the air around it.

In the air around a cloud, water is a gas in the form of water vapor. Inside the cloud, cooler temperatures have transformed water vapor into a liquid. This liquid is in the form of millions, billions or even trillions of tiny water droplets called cloud droplets. Scientists call this process condensation.

When water vapor in the air condenses into tiny cloud droplets, those droplets become visible. What we see is a cloud. Whether that liquid water will fall to the ground as rain depends on many factors.

Cloud droplets are very tiny and weigh very little. In a cloud, they float with the wind or simply hang in the air. In addition, updrafts (winds that blow upward from the surface of the Earth) also help keep droplets suspended within a cloud.

To fall to Earth, cloud droplets have to become heavier. If they combine with other droplets or if more liquid water continues to condense out of the air, they eventually become heavy enough to form drops that fall to Earth as rain. The scientific word for rainfall is precipitation.

Once droplets grow into drops and fall to Earth as rain, it will continue to rain as long as conditions in the atmosphere keep causing water vapor to condense into liquid water and grow into drops heavy enough to fall as rain.

So how much rain can a cloud produce? This is perhaps a better question than how much rain a cloud can hold. Scientists estimate that one inch of rain falling over an area of one square mile is equal to 17.4 million gallons of water. That much water would weigh 143 million pounds!

177 Join the Discussion

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    • We’re so glad you liked today’s Wonder of the Day® about rain clouds, Jazmine Crystal! Thanks so much for leaving us this comment to let us know you stopped by Wonderopolis today! :-)

  1. Love the Wonder of the Day- I am a 5th grade teacher in Florida and this is right down our alley! Can’t wait to share with my students. Keep up the GREAT work!

    • Thanks for the awesome feedback, Sue! We’re so happy to hear that you are engaging your students with WONDER! :-)

  2. That is so cool how you are telling us about how much rain can be held in a cloud…. I can’t wait to see what tomorrow is…

    • We’re so excited that you can’t wait to visit Wonderopolis again tomorrow, Sydney! We share that excitement with you…we can’t wait, either! :-)

    • Your comment made our day, Vincent! Thanks for letting us know that you love exploring the Wonders of the Day in Wonderopolis! :-)

  3. Dear Wonderopolis,
    We loved the wonder of the day! We tried the experiment and were amazed at how many water droplets the cotton ball could hold. We can’t even imagine how many droplets would be in a sky full of clouds. Thanks for the wonder today.:)

    • We’d like to thank YOU for visiting today’s Wonder and leaving us a comment to let us know how your experiment went, Mrs. Smith’s Grade 2,3 Class! We think that is SO NEAT! :-)

    • Hello, Shirley! Thanks so much for sharing what you know about clouds! We think you are a GREAT Wonder Friend! :-)

    • Hi, Mak! It’s not just 143 pounds…it’s 143 MILLION pounds! That’s a LOT of water! Thanks so much for visiting today’s Wonder! :-)

    • We think that was cool to WONDER about, too, Cheyenne! Thanks for letting us know what you liked learning in Wonderopolis today! :-)

  4. Hello,
    I don’t like rain at all, but we have to have it because it saturates plants. Rain is a form of Weather. It was so cool to find out a cloud can hold 143 MILLION POUDS OF RAIN!!!!!!!!!! Rain droplets are very small and weigh VERY little. Clouds can hold much more water than you think.

  5. Wow
    I never thought that the clouds could hold so much water. When I look at clouds that are gray I wonder why they are gray instead of white when they have rain. Also forecasts say what the weather will be for the whole week, do you know how they find that out?I like how it starts out as vapor then turns into water droplets.I can`t wait to see tomorrows day of wonder!!

    thank you for making me WONDER

    Team Clark 19

  6. Hi there!

    WOW!!! That is so cool that a cloud can drop 17.4 million gallons of water one square mile!! You know what, I hate rain but the one thing I love to do is to dance in the rain!!! It is also really good that it rains because you are right living in a dried up world would STINK!!! It is so cool how the air around us is just water vapor! If droplets are very tiny and way almost nothing, how much would they weigh? I wonder if the weather forecast people would know how much they weigh?

    Well thank for keeping me wondering!!

    • We think dancing in the rain sounds AWESOME, Team Clark #9! We agree with you, too, living in a dried up world without rain would stink! We bet meteorologists (the people who forecast the weather) would have a pretty good idea how much a tiny droplet of water vapor weighs…they have to learn ALL ABOUT the weather for their jobs! :-)

    • We’re REALLY, REALLY happy to hear that, Christina! Thank you for letting us know you stopped by today’s Wonder by leaving us this AWESOME comment! :-)

  7. Hello Wonderopolis!

    Sometimes I do wish that the weather would always be sunny. Other times I love when it rains. I really don’t like it when it’s sunny right after it rains. The ground is all wet and soggy so all you can do is sit inside and look at the sunshine. One time I actually did the cotton ball experiment. It was interesting because you would never think a cotton ball would hold so much water. I think it’s really cool that a cloud can hold 17.4 gallons of water. I used to never care about clouds but once when my family was driving somewhere my sister saw a heart shaped cloud. Sometimes it’s fun to just sit in your backyard and guess what shapes the clouds are.

    Thank You for making me wonder,

    Team Clark #20

    • Guessing what shapes the clouds are is one of our FAVORITE things to do, Team Clark #20! It’s fun to WONDER that way! We think how you described what it’s like when the sun comes out after a rain shower is AWESOME! :-)

  8. Hi WONDEROPOLIS ! I really liked the video. The weather was really cloudy. I can not believe how much water clouds can hold that much water! How much water vapor would that be? I thought a cotton ball could only hold about 10 drops of water but it actually holds 200! Imagine how much in a whole cloud! A Trillion!
    Thanks for the information!

    • Thanks for letting us know that you enjoyed the video for today’s Wonder, Team Clark #15! We think it’s really cool that you guys did the cotton ball experiment! :-)

  9. Hello,
    That is very interesting that one inch of rain over one square mile is equal to 17.4 million gallons of water! I did not know that it would weigh 143 million pounds!! Clouds are very important to saturate the plants. What part of the atmosphere are the clouds?

  10. Hi. Weather to me is very cool. I learned a lot about weather. I learned things like: the word condensation. The rain droplets have to get heavier to fall onto the Earth. I also learned that one inch of rain falling over an area of one square mile is equal to 17.4 million gallons of water. And that much water can weigh about 143 million pounds. Teamclark21

    • All those facts about clouds are GREAT, Team Clark 21! You sure did learn a lot in Wonderopolis today…thanks for visiting! :-)

    I think that it is amazing how much it can rain. I watch the weather everyday. The weather gives the world there forecast for the day and it said today was rainy. Then I went on Wonderopolis and I thought that was funny that it was about rain. Did you guys do that on purpose?

    Signing Off,
    Team Clark 6

  12. Hi ;)
    Wow that is so cool. I thought that clouds where made of water not water vapor. I would love to learn more about condensation. I wonder if all clouds hold a lot of rain or just a little. I would love to know how they make a weather forecast. Do you have videos on sun or something like that. Sometime I will want to do the try it.
    Thanks for the wonder of the day
    -Team Clark 8 ;)

  13. I think that this topic is good and fun to study and is showing how the clouds move and how they like filled and getting ready to rain.
    I also learned so new facts about rain I didn’t know before.
    I also learned that this site is a good site to find facts on the topics you guys have.

    Thanks, Wonderopolis

    • We’re so happy to read your comment, Team Clark #1! It sounds like you learned a LOT by exploring this Wonder today…we think that ROCKS! :-)

  14. Hi!
    Today’s wonder was cool! I didn’t know that clouds could hold that much! 143 million pounds of water is a lot and that sounds very very VERY heavy! 17.4 million gallons of water seems like a bunch of water, I wonder how much water people use every day and I wonder if everyone used water from the rain and not for lakes how much water would be left or if there would be any water left? When the forecast says the weather will be rainy, I now know how much a cloud holds.

    • We’re really loving all these SUPER cloud comments today, Team Clark #11! Thanks for sharing YOURS with everyone in Wonderopolis! :-)

  15. Hello Wonderopolis

    I liked learning about the weather. I didn’t know that clouds held 17.4 million gallons of water. How long does it take for the cloud to replenish its water? And how high are the rain clouds?

  16. Hi,
    I can’t believe how severe the weather can be when it comes to rain! Who would have thought that the clouds could let off 17.4 million gallons of water in just one square mile! Also that after it rains, most of the water is vaporized. I loved that I learned that water is in the air. You helped me a lot because I always had that wonder. :)


    • Well, we’re glad today’s Wonder was about clouds then, Team Clark 10! It makes us happy to hear from Wonder Friends like you who tell us that a Wonder of the Day® is something they’ve always WONDERed about! :-)

  17. Hi Wonderopolis!

    A few Questions I had as I was reading was:
    -If scientists estimate that one inch of rain falling over an area of one square mile is equal to 17.4 million gallons of water, doesn’t really just depend on the size of the cloud?
    -And why would the world be dusty without rain? I learned many things such as:
    -I am surrounded by water, from solids, liquids, and gases.
    -In a cloud, droplets float with the wind or simply hang in the air.
    -Water droplets is in the form of millions, billions or even trillions of tiny water droplets called cloud droplets.

  18. Hello, Jessie, Malley and MJ! Thanks for visiting Wonderopolis today! You are ALL great Wonder Friends! :-)

  19. Thank you so much for putting this one up it was the best ever!!! I love wonderopolis so much that I am going to get online every day thanks to you wonder girls and guys!!!!

    • We’re really glad to hear that, Justin! Thanks for telling us that you thought today’s Wonder was the best one ever! :-)

    • That’s such a super question, Kriss! We think storm clouds appear dark because of all the heavy water droplets clinging together inside of them. It makes it harder for the sunlight to shine through! :-)

  20. Hi, wonderopolis what was the video about? It was just clouds floating in the air, but I read about and I understood. I think tomorrow’s wonder is about berries or I wonder if is about dogs because on the hint it said HOUNDING. I don’t know which one to choose, maybe I’ll stick with the one or maybe I’ll use both because you never know if you’re right on one and you’re wrong on the other and I double love the video absolutely love, especially the writing.

    • Thanks so much for your comment, Crazy Gurl! We thought the video for today’s Wonder illustrated rain clouds very well! We appreciate your guesses about tomorrow’s Wonder, too! :-)

  21. The weather on the earth is so unique and different! I love to research
    about lightning and rain. I wonder how it replenishes it’s water?
    Wonderopolis is truly splendid! I have looked at many of your videos! They are all very intresting. Where do you decide what topic you are going to make? What inspired this website? Here is a fun fact for you!
    America was named after the first person that realized that America wasn’t India. His last name was Amerigo.

    • Thanks for sharing that cool fact about America, Team Wilch #4! Did you know that many of the ideas for Wonders of the Day come from the creative, WONDERing minds of Wonder Friends just like YOU? It’s true! You can tell us what you are wondering anytime you like by leaving us a comment or by clicking on the “nominate” button at the top of every page in Wonderopolis! It’s fun and super easy! :-)

  22. Hi. I think this is cool because clouds are part of the water cycle. I learned that raindrops have to be heavy to fall to the ground and that clouds are really a bunch of rain droplets! I think that condensation is very interesting. Do you know how much a rain droplets have to replenish before it rains again? Thanks for the wonder!

    Team Wilch8

  23. WOW 143 pounds of water can be held in a cloud.17.4 is a lot of water.It is really cool that air is filled with water.If all 17.4 gallons of water came crashing down at your city I bet the city would be a disaster.My dad checks the forecast everyday if it is raining so we can be safe.

    here is a question

    Can you feel water vapor?

  24. Dear Wonderopolis,
    My class and I LOVE Wonderopolis so much! I was very interested to know this much about clouds and weather, since I like science. I have one question, though. I want to know if more rain comes out of the clouds according to which season we are in. Such as in sometimes spring we get more rain than in fall. It amazes me how much a cloud can hold! 17.4 million! Finally, I loved the experiment about how we can compare cotton balls to clouds! Thanks for being so great!

  25. Dear Wonderopolis,

    Thank you so much for that information! Now I know so much more about clouds. I never knew that it could rain that much. It’s really interesting that water is all around us in so many different forms. I have a question how much does a cloud weigh? I love the rain, it’s so much fun to play in it. Rain doesn’t always have to bring you down it can be fun! Where has the highest amount of rain been? I think that it’s in the Amazon Jungle! Do you know how often it rains there?
    Thanks Wonderopolis!

  26. Hi Wonderopolis!

    That is so cool that 143 million pounds of rain fall in 1 square mile!
    Why is it that when we go outside in a rain storm that we don’t get hurt from the rain. How does the weather man on T.V. know what the forecast will be? It would probably hurt if a cloud just fell on you. :) How does fog not hurt if a cloud weights 143 million pounds?

    Team Wilch 9

  27. Nice wonder!!!!! I love clouds do you?! I tried the experiment at school and the cloud held more than 200 drops! Me and my brother did this when we got home from school.
    Thanks Again Wonderopolis!

    Landon Kushneryk

    • WOW, Landon! It’s so cool that you did the cloud experiment TWICE today! Thank you for sharing what you learned in Wonderopolis at school with your brother at home and helping him WONDER a bit today, too! :-)

    • That’s a SUPER question, Selina! We will both have to do a bit more WONDERing about that one! Thanks so much for hanging out in Wonderopolis today! :-)

    • Hello, Lane! The video for today’ Wonder is just a really cool time lapse (long periods of time condensed down and/or sped up to make a short video) of clouds moving across the sky and a storm moving in! Sometimes we choose a video that just goes along with the Wonder, but doesn’t really explain anything…sometimes the videos are just neat to watch! :-)

  28. I have always wondered about rain because I am in science class in third grade and I live in MD. We are working on it.

    • That’s really AWESOME that you and your science class are studying about rain, Jaidyn! Thank you for letting us know a little more about yourself, too! We bet it’s fun to live in Maryland! :-)

  29. Why, hello there, wonderpoilis.
    I am johannah but you can call me hannah, soo I am 9 I am in grade 3. I LOVE SCHOOL! AND I ALSO WANT TO KNOW HOW MUCH RAIN CAN A CLOUD HOLD??

    • Hi, Johannah! Thanks for leaving us this AWESOME comment! We really appreciate it! We encourage you to re-explore this Wonder of the Day® to learn how much rain a cloud can hold! Happy Friday! :-)

  30. Hi Wonderopolis!!
    This was a way cool wonder!! I did the experiment at home and my cotton ball held 396 drops if water. My Mom thought I was just playing with water for no reason. When I told her the real reason she joined right in. I think tomorrows wonder will be about how fruit juice is made. This is the coolest website in the wonderful universe!
    Your WONDERful friend,
    Food Allergy Girl

    • We LOVE hearing that you and your mom tried the cotton ball experiment together, Food Allergy Girl! 396 drops of water is a LOT! Thanks for being a GREAT Wonder Friend! :-)

  31. Dear Wonderopolis,
    Cool wonder! A cloud can hold as much rain as it can until it can’t hold anymore and it has to let it out or “cry”
    Paige ;)

    • We like the way you phrased that, Paige! We will think about clouds letting out a good cry now when it rains in Wonderopolis! :-)

  32. P.S. I am allergic to milk for any of you who were wondering! Any questions can be posted on this website!

  33. Hi wonderopolis!
    What I know is that the rain evaporates and goes up to the clouds and then when the cloud gets full it all comes down again. That’s when it rains!

  34. Hi, I love all the wonders. I am in grade 3. I am friends with Johannah. All of the wonders are cool and different every day. I love wonderopolis!

    • What a GREAT comment you left for us, Lexy! Thank you very much! We think it’s COOL that you’re friends with Johannah and we’re REALLY happy that you love Wonderopolis! :-)

    • We really like your comment, Niki! We thought it was super FUN to learn new things about clouds and we’re glad you did, too! THANK YOU for being such a GREAT Wonder Friend! :-)

  35. Señora Waingort’s grade 2 class is wondering how many water drops can fall from one cloud? Did you know clouds are thick air? How fast can a cloud move?

    We’ve been learning about water in science. Warning: clouds can turn into air monsters!

    • We think it’s AWESOME that you guys are learning about water in science, Señora Waingort’s class! We think air monsters sound a little bit scary…we didn’t know that about clouds! Thank you for teaching US something new today! YOU GUYS ROCK! :-)

  36. Hello, this is Olivia DiPaolo from Mrs. Caplin’s 5th grade class. We are currently doing an expository project and mine is about the clouds and predicting weather. I was wondering if you had anything about clouds or predicting weather that may be resourceful to me. This wonder of the day has helped me with my expository project, thanks for this awesome wonder.

    • Yes it is, Matthew! Thanks so much for visiting this Wonder and for leaving us this AWESOME comment! We’re glad you learned some cool new facts about clouds! :-)

    • We’re super glad you liked the video for this Wonder of the Day®, Ninja! Thanks for letting us know! :-)

    • That’s a really awesome question, Jackie! We encourage you to re-explore this Wonder of the Day® to learn how clouds hold rain! Have a WONDERful day! :-)

    • Thanks for your comment, Jeff! We love WONDERing with great Wonder Friends like you! There’s no limit to the power of our imaginations, and we have so much fun being curious friends in Wonderopolis! :)

    • What a great Wonder from our friends in Mrs. Foster’s class! HOORAY! We like how you are using your imagination about clouds and water today! :)

      When the cloud is “holding” the rain, it’s not in the form of water (we’re used to seeing and feeling rain as water when it falls from the sky). However, just like a balloon is blown up with air, or gas, a cloud holds the rain in the form of gas. This allows it to look nice and fluffy to us– the cloud is actually filled with gas. When the rain falls from the sky, it goes through a chemical change and falls in the form of water! We hope this helps you imagine those big clouds in the sky, filled with rain in the form of a gas. :)

    • HOORAY, we’re so glad you learned something new about those cool, fluffy clouds, Jalenlee! Thanks for sharing what you learned– you’re a great Wonder Friend! :)

    • We’re so excited that you learned about what clouds can do, Jalenlee1! It’s amazing to discover the science behind those big clouds and how they store gas before it becomes rain! :)

    • Great recommendation, Jalenlee! We are glad you are spreading the Wonder– it’s fun to learn together! Thanks for being a great Wonder Friend! :)

    • It all depends, Pastrana 199! Sometimes it can rain for many days straight, and other times it’s nice and sunny! However, today it looks like rain… but we’ll still have fun indoors! :)

    • Thanks so much, Wonder Friend from Mrs. Mann’s Class! We are so excited to know that you have been WONDERing with us about those big clouds up in the sky! We hope your day is bright and sunny and filled with Wonder! :)

  37. Hi, wonderopolis! Did you know that when you see rain coming, and you can smell it also? Well, the smell isn’t coming from the sky. It is actually coming from the ground. You see, the moisture in the air causes the moisture from the ground to come up and make that smell. Thank you for today’s wonder! :) ;)

    • Hi Berkleigh, what a SUPER fact! Thank you for telling us about the moisture in the air and the moisture in the ground. Our senses, especially our ability to smell, are on high alert when it’s about to rain! We love WONDERing about science with you, Berkleigh! Thanks for sharing your comment- what a SUPER connection! :)

    • Hi Emma! Thanks so much for WONDERing with us! We’re so glad that you’re learning and WONDERing with us! Keep WONDERing! :)

  38. Dear Wonderopolis we loved this video. It was soooooooooooo funny. We learned that water is a form of gas. Thanks for sharing.

    • Thank you for WONDERing with us today, Evan.W and Andrew.W! We are so glad that you enjoyed the video! Keep WONDERing, Wonder Friends! :-)

  39. Dear Wonderopolis we loved Fluffy Mc cloud in the video. It was so funny. We learned that water is a gas in a form of water vapor. Thanks for sharing Wonderopolis. Bye.

    • WONDERful, Evan.W and Andrew.W! We are so glad that you enjoyed this Wonder Video, and that you learned something new today! Thanks for WONDERing with us today, Wonder Friends! :-)

    • WONDERful question, Jorden! We like to select videos that are entertaining, yet make you want to explore more about the Wonder. We hope you enjoyed it! Thanks, for WONDERing with us today! :-)

  40. I learned that water comes in many forms. Water comes in a solid (ice), water comes in a gas (steam), and water also comes in a liquid (water we drink).

    • Welcome, alysa carpenter! You’re right in that clouds don’t hold water. It’s not the average rainfall that is 17.4 gallons, but actually that “one inch of rain falling over an area of one square mile is equal to 17.4 million gallons of water. That much water would weigh 143 million pounds!” Can you believe that? Thanks for WONDERing with us! :)

  41. I learned that scientist have discovered that an inch of rain of on square mile is 17.4 million gallons of water and that much water can weigh up to 143 million pounds . It was really awesome to learn that .

    • Hello, Leah! It sounds like you really learned a lot of interesting facts from this WONDER! Clouds are WONDERful to learn about. Great WONDERing! :)

  42. I learned that a cloud dosen’t really hold water like a bucket. There is water all around us and we don’t even know it. Water comes in three different types and those types are 1. Ice ( which is a solid.) 2. Water ( like what you drink which is a liquid.). 3. Water vapor air ( which is a gas.) These are very important things that I needed to know.

    • Welcome WONDER friend, jahiquez! Clouds actually do not hold water. Instead there are forms of water all around them. Keep up the WONDERful WONDERing and visit again soon! :)

  43. How does the cloud get a lot of water?Not evaporation I mean how does it hold all
    of the water.Plus how does water get evaporated?!

  44. I learn that clouds droplets are very tiny and they weigh a little.I learn that if you see a cloud roll in a sunny day that means rain is on the way.

  45. I learned that one inch of rain fall over a certain area is a lot of water! I also learned that that clouds don’t “hold” water.

  46. We loved this article! We learned so much about the water cycle. Right now we are not worried about the rain going away, but instead the snow! We wonder what causes thunderstorms and how much rain falls in a year?

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Have you ever wondered…

  • How much rain can a cloud hold?
  • What is condensation?
  • When will a cloud produce rain?

Wonder Gallery

rain clouds_shutterstock_55994950Vimeo Video

Try It Out

Ready for some fun on a cloudy day? Find a rainy day friend or family member and try out one of more of the fun activities below:

  • Do you like cloudy days? We do! Sure, we love the sun, too, but it can be fun to relax on a cloudy day and simply gaze at the clouds as they pass by. Do you ever look at clouds and see shapes or objects in them? As clouds move, they take on many interesting shapes. Sometimes they resemble bunny rabbits. At other times they may look more like wispy trees. Get some cotton balls, construction paper, markers, glue and glitter and make your own cloudy picture. Glue pieces of cotton ball to your construction paper. Use markers and glitter to complete your picture. Can you make your clouds look like something in particular, such as an animal?
  • What do you like to do on a rainy day? A lot of kids have “rainy day” plans. Those might consist of things to do inside on a rainy day. But what about a “rainy day” list of things to do outside on a rainy day? It can be fun to dance in the rain. There are many other things that can only be done on rainy days. Rainbow chasing, for example, is much easier on a rainy day. What other things might you look forward to doing outside on a rainy day? Brainstorm and come up with a special list of things you can look forward to doing outside the next time the clouds let loose!
  • Up for a fun and simple science experiment? All you’ll need are water, an eyedropper and some cotton balls. This experiment will show you that cotton balls, like clouds, can hold more water than you might think. During this experiment, you will hold a cotton ball over a bowl. With an eyedropper, you will slowly begin to add droplets of water to the cotton ball until it gets saturated. You’ll know it’s saturated when water begins to drip into the bowl as if it’s raining. Before beginning, though, estimate how many drops you think the cotton ball can hold before it becomes saturated. Write down your estimate and then get started. The purpose of the experiment is to put as many droplets of water into the cotton ball as you possibly can. Using the eyedropper, begin adding droplets of water to the cotton ball. Keep count of all the droplets. Write them down on a piece of paper if you need help keeping track. As the cotton ball begins to fill with water, feel free to move the cotton ball or the eyedropper, so that you can put droplets of water into all the areas of the cotton ball. Stop counting when the cotton ball becomes fully saturated and begins to “rain” into the bowl. So how accurate was your initial estimate? Don’t worry if you underestimated how much water a cotton ball would hold. Most kids guess very low (less than 25 drops). Were you surprised by how many water droplets a cotton ball could hold? If you used the smallest droplets possible and completely saturated every area of the cotton ball, it’s possible for a cotton ball to hold over 200 droplets of water! Of course, your first try at this experiment might not have given you a result of 200 or more droplets. Just like rain clouds, cotton balls might hold more or less droplets for a variety of reasons, such as the size of the droplets, the size and thickness of the cotton ball and whether or not all areas of the cotton ball were saturated.

Still Wondering

In ReadWriteThink’s Lonely as a Cloud: Using Poetry to Understand Similes lesson, children identify similes in poetry and gain experience in using similes as a poetic device in their own writing.

Test Your Knowledge

Wonder What’s Next?

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