Light and Dark Bottle Heat Absorption Experiment For Kids

You’ve likely heard recommendations to wear white clothing in hot weather because it reflects heat and keeps you cooler while dark clothing absorbs heat and can make you feel hotter. But have you ever experimented with the science behind this principle to find out if it’s actually true? 

We’ve created a simple sustainability science experiment to observe how dark materials absorb more heat than light materials. Try this sustainable science experiment for kids to practice important critical thinking skills and better understand this important concept in considerations about climate change. 

This post includes affiliate links.

Back when I played sports as a kid, I remember contemplating what uniform to wear for a game on a hot summer day. We always defaulted to the white jerseys instead of the dark jerseys because they kept us cooler (or so we assumed). We never tested this thermodynamic principle about the difference in heat absorption rates between light and dark colors, but it made sense so I believed it to be true. 

As we learn more about climate change and rising global temperatures, this principle about different rates of heat absorption plays a pretty significant role in assessing the implications of a warmer planet. We see its relevance in ways both large and small. 

In warm climates, for example, homeowners often paint their homes lighter colors to reduce heat absorption from the sun. This helps keep their houses naturally cooler and reduces the amount of energy-guzzling air conditioning they might otherwise use to cool their homes. 

Meanwhile, we construct solar panels with dark materials to increase heat (i.e. energy) absorption and maximize the efficiency of the energy production process.

On a larger scale, bright white ice caps reflect a lot of sunlight. This reduces the amount of heat absorbed by the planet and slows the pace of global warming. As the ice caps melt and we lose their reflective benefits, we enter a feedback loop through which global warming happens more quickly, ice caps melt faster, and the cycle continues and speeds up. 

These are just a few of many examples where heat absorption rates carry meaningful consequences in our considerations of how to address climate change.

As we teach our children about climate change, we can offer some really fun and educational sustainability science lessons for kids about environmental matters to help them understand why sustainability is so important. These experiments also offer opportunities to learn critical thinking skills. 

We’ve created a simple light and dark bottle heat absorption experiment to demonstrate how dark materials and surfaces absorb more heat than light materials and surfaces. With just a few simple things you probably have around your house, try this sustainability science experiment to better understand how thermodynamics can be used to address climate matters (and why we should wear light-colored clothing in the summer heat). 

Renewable Energy At The Tokyo 2020 Olympic Games

This heat absorption experiment is part of our Renewable Energy Workbook For Kids that we created to highlight and explain the commitment to renewable energy made by the International Olympic Committee during the Tokyo 2020 Summer Olympics. 

In this fun and educational renewable energy activity book, you’ll find:

  • A crossword puzzle to learn more about renewable energy terms and principles
  • A recommendation of a great picture book, along with discussion questions, that incorporates renewable energy and environmental justice through the eyes of a young and innovative boy in India 
  • The light and dark bottle heat absorption experiment we describe below
  • A sustainability science project to design a solar oven at home (that may include eating s’mores – no one will complain about that)

You can use the instructions below to create your own light and dark bottle heat absorption experiment with the youngsters in your life. If you’d like additional renewable energy activities and another solar energy science experiment to go along with this science activity, download the full workbook. It includes great resources about renewable energy for kids that are easy to print out and use at home, in the classroom, or wherever you have curious young minds ready to explore the science of solar energy. 

Light and Dark Bottle Heat Absorption Experiment For Kids

As mentioned above, dark colors absorb and hold heat better than light colors. That dark materials maximize heat absorption is an essential characteristic for designing efficient solar panels. 

Try this light and dark bottle heat absorption experiment for kids to observe different heat absorption rates. This simple sustainability science experiment also provides opportunities to collect and analyze data; two skills necessary for becoming an effective critical thinker.

Be sure to download the Renewable Energy Resources Workbook to also get the discussion questions for this experiment. We’ve included several questions to inspire critical thinking about the results of the experiment.

Notes About Materials and Tools for the Heat Absportion Experiment

You likely already have most of the supplies in your home to perform this heat absorption experiment with your young learners, though you may need one or two additional tools to complete the sustainability science experiment. Here are a few things to consider about the materials to perform this heat absorption science experiment with kids.


You will need three thermometers to complete the science experiment. Two of the thermometers must be tall enough to stand inside your glass jas or bottles. We prefer these Liquid-In-Glass Laboratory Thermometers, but you’re welcome to use whatever you have on hand if you already own something that will do the trick.

Glass Jars or Bottles

Most of us have lots of glass jars and bottles in our homes already. Many grocery items come in glass jars and bottles. Here is a guide to cleaning upcycled glass jars and bottles so they are nice and clean for your experiment.

Black Spray Paint

Any paint that sticks to glass will work for this experiment. We used a simple flat black spray paint but use what you have available to you. You may even be able to request a bit of leftover black paint from a neighbor in a Buy Nothing Group, a Facebook Marketplace group, or a Nextdoor Community.

Let Us Know How This Experiment Works For You

If you try this sustainability science experiment, let us know how it goes. Share in the comments or post on social media and tag us @RaisingGlobalKidizens on Instagram or Pinterest so we can see it. We love seeing you bring our activities to life in your home!

If You Liked the Light and Dark Bottle Heat Absorption Experiment for Kids, You May Also Like:

Renewable Energy Sustainability Science | Solar Energy Activities for Kids

Sustainable Science Experiment | Landfill Emissions

How To Build A Solar Oven + Solar Energy Science Experiment For Kids

Light and Dark Bottle Heat Absorption Experiment For Kids

Light and Dark Bottle Heat Absorption Experiment For Kids

Prep Time: 30 minutes
Active Time: 3 hours
Total Time: 3 hours 30 minutes

We’ve created a simple sustainability science experiment to observe how dark materials absorb more heat than light materials. Try this sustainable science experiment for kids to practice important critical thinking skills and better understand this important concept in considerations about climate change.


  • 2 identical, clean glass jars with labels and lids removed
  • Aluminum foil
  • Black spray paint
  • A sunny day


  • 3 thermometers
  • Pencil


  1. Clean and remove labels and lids from two identical, clear glass jars.
  2. Paint one of the jars black and leave the other jar clear and colorless. Be sure to follow all safety and procedural guidelines provided on the paint packaging when painting your jar.
  3. Once your painted jar has dried, place both jars right side up and cover each opening with aluminum foil.
  4. Using a pencil, poke a hole in the center of each aluminum foil lid and slide a thermometer into each jar.
  5. Record the initial air temperature within each jar on the data table provided.
  6. Place both jars outside in direct sunlight.
  7. Place the third thermometer near, but outside of, the jars. This will serve as your control. Record the initial air temperature outside of the jars. 
  8. Observe and record the air temperature of each thermometer every 20 minutes for the next 3 hours.

Recommended Products

As an Amazon Associate and member of other affiliate programs, we earn from qualifying purchases.

About The Authors

Jen Panaro

Jen Panaro, a co-founder of Raising Global Kidizens, is a self-proclaimed composting nerd and an advocate for sustainable living for modern families. She’s also a serial library book borrower and a messy gardener.

As a mom to two boys, she is passionate about helping families be more responsible stewards to their communities and the planet. She also owns Honestly Modern, an online space focused on eco-friendly living for families.

Jess Purcell

Jess Purcell, a co-founder of Raising Global Kidizens, is a science educator who is dedicated to making the science of sustainability accessible to all learners. She creates sustainability science lessons and nature activities written for students of all ages to be done in the classroom or at home to foster critical thinking skills and a love of the natural world. You can find more of her work at Thoughtfully Sustainable.

Jess lives in central Pennsylvania with her husband, two kids, and two cats and can usually be found outside, working out the kinks of an experiment, upcycling trash into “treasure”, hiking with her family, or attempting to read a book while being cajoled into a game of hide-and-seek.

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.