Apr 102016

Hot Air Cold Air Science Experiment

Both of my boys are SO into STEM (Science, Technology, Engineering and Math education) with a huge emphasis on the science part.   It’s funny because I hated Science class when I was in school.  Hated it! Now that I am an adult I have a whole new appreciation for it and am trying to catch up with a lot of what I missed while I was sleeping in class all those years ago.  Lucky for me, my boys love all things science related and get so excited when we do science experiments at home. This hot air/cold air experiment was a lot of fun to do with the kids and the results are absolutely fascinating.

Here’s what you need:

  • Two containers
  • Empty drink bottle
  • Large balloon
  • Ice cubes
  • Hot and cold water

**Note, there is no need for the stick, I just didn’t want my hands blocking your view.

Here’s what you do:

1. Fill up one of your containers 3/4  of the way with ice cubes and water.


2. Fill your second container with a very hot water.
3. Stretch out your balloon and maybe blow it up and deflate it a few times.
4. Stretch the opening of your balloon over the top of your empty bottle.


5. Place the bottom of your bottle into the hot water and see if anything happens to your balloon.


6. Now place the bottom of your bottle into the cold water and see if anything happens to the balloon.
7. Switch back and forth between the hot and cold water and watch your balloon inflate and deflate.


Ask your children questions about this activity:

Q- Why do you think the balloon inflated in hot water?
A- When the bottle is placed in hot water, the air inside the bottle gets warm and needs more room to expand
Q-Why do you think the balloon deflates when the bottle is placed in cold water?
A- The cold air contracts and needs less space than the hot water

Do your kids like doing science experiments at home?

  108 Responses to “Hot Air/Cold Air Science Experiment”

  1. Awesome science experiment and got to keep this in mind maybe for a future science fair experiment.

  2. This would be such a fun experiment for a rainy day. Tucking this one away for the future.

  3. My oldest is really into STEM learning as well. We will be touring colleges soon that have a strong focus on STEM, especially ones that encourage women to apply.

  4. We are big on STEM in our house. My kids will love this!

  5. This is PERFECT for my 6 year old. Thanks for the idea!

  6. My grandkids love science experiments and they would love this one. A few days ago they made homemade lava lamps. I’ll show this one to my daughter.

  7. I’ve actually never seen this one before … it’s awesome! I’m like you, too – I never really cared for science when I was young, but now I find it really intriguing. I’m definitely going to do this experiment with my grandson.

  8. You can’t go wrong with science and kids. It’s utterly fascinating, you’re right!

  9. I’ve always loved doing DIY science experiments like this with the kids. It’s a much better way to learn than just sitting and staring at words on a page.

  10. This is really great. I can not wait to try it with the kids.

  11. I’m a science teacher by day, so LOVE your experiment! Hands-on is always the way to go – kids remember much better and it makes a stronger connection!
    Karen | GlamKaren.com

  12. My boys are always doing expriments too! They are older so they see things on YouTube and then try to do them without asking! I think we put a stop to that now. I’ll show them this one, I bet they will love it!

  13. What a fun science experiment. Something like this would have been perfect when I was homeschooling!

  14. This is such a cool and simple experiment! My kiddos would love it 🙂

  15. My kiddos LOVE anything to do with STEAM education and inventing their own experiments! We haven’t tried this one yet, pinning for later!

  16. How cool is this? My kids do some pretty awesome science experiments at school. It just seems we don’t have enough time at home to try experiments on the evenings and weekends. I’ll have to save this one for the summer!

  17. This is fun! Isaak did a different science experiment 2 years ago with a balloon blowing up. We’ll be working on different science experiments soonish. The boys have a science fair every year at school.

  18. With it being school holidays, this will be a great way to keep the kids entertained with the added bonus of extra knowledge ☺

  19. Yes, our girls have always enjoyed doing at home science experiments. This one looks like fun for all ages. Easy enough for younger, but interesting enough for older.

  20. As an engineer myself, I absolutely love exposing my kids to at-home science experiments like this! I love this idea that teaches the expansion/contraction of air! What a fun way to incorporate play & learning! Thanks for sharing this!

  21. My boys would love this. The other day they were trying a bottle with a balloon outside in the sun.

  22. I’m always looking for new educational projects to work on at home with the kids. Thanks for the tip! My kids will love giving this a go!

  23. I need to try this over the summer with my kids!

  24. What fun!!! I’m going to share this with a lot of people who have boys!!

  25. I love seeing STEM projects for kids on line. I think girls, especially, should be encouraged to do these things!

  26. This looks like so much fun!! I can’t wait to try it at home with my two little science enthusiasts! 🙂

  27. I have some homeschool friends that will be using this as their next science experiment. What a great visual learning tool.

  28. This is so awesome. Science activities make learning fun.

  29. This is such a cool science experiment. I used to hate science experiments in school because I was really bad at science, but you make this look fun! Great post! xx felinebykatsairs.com

  30. This is so cool! My 9 year old would love this. I am definitely going to do this soon with her. She is ALL about the experiments.

  31. At home science experiments are so much fun. I think it is a great activity to spark your kid’s creativity and logical thinking.

  32. My siblings would LOVE this! I’ll share it with them. Thank you!

    Jasmine / http://www.jasminekeclipse.com

  33. I think my children would enjoy this project very much, they are also into STEM.

  34. I remember doing this experiment as a kid in science class! So fun!

  35. oh what a cool experiment.its good to do these kinds of experiments with kids.its easiest way to teach them

  36. Adding this to our science experiment board on pinterest. My kids love science and this would be such a great hands on learning experience.

  37. This is a really neat little experiment. I think my kids would really enjoy it. Thanks!

  38. Isn’t it funny that the things we dislike as a child we end up liking as an adult. Glad that you get to enjoy STEM together!

  39. I was gonna say that this made me think about my grade school science teachers. Learning should be made fun & easy. This experiment looks less intimidating when done at home instead of in school, lol. Or maybe that’s just me.

  40. That’s how science can make a little thing for our learning. It would be fun to do this activity with my son for more learning about experiment.

  41. This is a super fun idea, I Love having some educational fun with my kids!

  42. How fun and easy my daughter loves stuff like this I saved to do with her ASAP.

  43. What an awesome idea! I wasn’t into science as a kid either but this is such a great way to get kids interested 🙂

  44. The school I work at is working on STEM certification, so this is a project that some of our teachers may be interested in. I’ll be sure to share! Reminds me of my science project days.

  45. i love this. It looks really fun. My kids are really into STEM too so I think this would be really fun for us all to do together!

  46. Such a fun little experiment for the kids to do. It really is amazing what you can teach them from home

  47. This is so cool!. I will try this and let my daughter do the experiment. 🙂

  48. My kids love to do science experiments and this one is a great one, I love it when they can find stuff around the house to use.

  49. Science is the best. Never made this one but loved the Volcano experiment.

  50. What a fun experiment to do with kids! It’s good to ask them questions to see if they understood the whole point of the experiment. My girls loved science experiments when they were younger too!

  51. This is definitely an experiment that will get young minds thinking! Great post!

  52. Great experiment… I don’t know about kids but I would love to try it. Thanks for sharing

  53. My kiddos would love to try this! I love anything on the weekends that keeps their minds going!

  54. Very cool! Next snow day we will do this. Because here is a fun science question: why do we still have freakin snow!!!?? It’s April! ha.
    I think I would have paid more attention in science class too, if we did fun experiments like this — but I don’t recall doing anything like this. Maybe just the volcano one and the teacher got to do that messy one!

  55. YES! We are Science geeks in my house. I’m like you – I hated Science as a kid – but I think it was all the boring teachers i had!

  56. I love doing science experiment when I was a kid. You can really learn a lot from this experiments.

  57. What a fun experiment. If I show this to my son he will undoubtedly tell me the entire science reason behind what happens.

  58. I saw my sister before doing that! Now, I really understand it more. Thanks for sharing!

  59. This looks like an awesome science experiment. Going to try this with my son!

  60. My 11 year old is very interested in science so he would really be interested in this. I might actually have him try it out this weekend.

  61. Very cool. SHould I have known that this happened? Lol. I hated science, too. I dread the science projects coming up.

  62. My kids love doing science experiments. We just made a rocket shoot off a couple times yesterday with some science stuff.

  63. What a cool experiment! My husband is kind of geeky and he would love to try this with the kids

  64. My Kids have always loved trying new experiments. I will have to get the supplies i need to do this on the weekend.

  65. I’ll be doing this experiment later this week with my son!

  66. This is absolutely a fun project for my kids. Can’t wait to tell this with them

  67. How cool…I think most kids love Science until they get to a certain age and then poof

  68. Cool science experiment – I should try this with my boys!

  69. This looks really cool, my son is heavy into STEM. He also loves science projects. We will give this one a go.

  70. I never cared for science class while I was in school either! Now that I’m an adult, I too have a complete appreciation for it! My kiddos love doing science experiments at home too and we’ll have to try this cool experiment!

  71. I used to love science projects when I was a kid though not so much now lol. Lovely experiment though

  72. This looks like a nice science experiment.
    Your write-up layout looks real nice also.

  73. My daughter would love this experiment! Saving for later.

  74. Omg I use to love doing these types of activities when I was a kid!! Might just have to do this with my daughter:)

  75. What a fun experiment! This is so awesome!

  76. How cool is this? I’m going to have to do this with the boychild. He loves experiments and this looks like a ton of fun. I’ll let you know how it goes

  77. This is such a cool experiment and activity! I am sure kids would love it!

  78. I love this experiment. I will try it out with my niece. She is really into STEM stuff, I think this will excite her.

  79. How fun! I have a couple of friends that homeschool their kids I’m going to forward this to them! Thanks for sharing!

  80. I love this! While we are homeschoolers, I often shy away from the science experiments. This one looks like one I can successfully do, and something my kids will love.

  81. That’s such a fun experiment for kids! I know the kids I used to work with would have loved seeing this.

  82. Oh, this looks like such a fun project. I actually miss the days when my kids had science and engineering fairs…I may have enjoyed it even more than they did. 😉

  83. This looks like it is such a fun experiment!!!

  84. Kids love this type of experiment (i know i used to.. =) ). I’ll give a try with my little sister, thanks for sharing!

  85. This is really a good project for my 8 years old niece and I bet this is so fun.

  86. My daughter is not old enough to understand the science behind this but she would love to see this project in action. I’ll give it a shot.

  87. What a great experiment! My sons would love to try it out! Thanks for sharing!

  88. What a fun activity that kids can participate in and learn from! I can’t wait to try this some weekend when Im babysitting my favorite 7 year old!

  89. That’s a cool experiment. My kids love science! We’ll try this experiment soon

  90. My son can’t wait to do this experiment!

  91. This is such a good experiment. I think kids would love this

  92. I have to show this to my daughter, she would love to try this.

  93. Such a fun experiment! I will try this experiment with kids and I’m sure they will love it!

  94. Cool experiment I use to be big on engineering and science.

  95. This is a cool experiment! My girls love doing things like this!

  96. Interesting experiment! Seems like it’d be fun for kids of all ages!

  97. How fun is this! I love experiments like this that are interactive for kids and they can learn something.

  98. Adorable, it’s so much fun when they are younger. The questions they have are so cute.

  99. LOVE that your boys are so into STEM! My son is a little on the younger side, but I think he would even have fun with this!

  100. What an awesome experiment. I’m going to try this with my kids on the weekend. 🙂 Bookmarking!

  101. This is such a classic science experiment, but still so fun for kids! I loved learning about all this and doing experiments as a kid.

  102. That is so cool! My kids are all about STEM activities…they are so fun to do with them.

  103. This was easy! I wish I was this savvy as a kid!

  104. I love Science experiments like this. It’s really cool and I’m sure my son would have a thousand questions afterwards.

  105. This sounds like a great experiment. My daughter would enjoy doing something like this I bet.

  106. No kiddos but my nephews definitely love experiments! Although theirs usually wreak havoc! LOL 🙂