Challenge your little ones to learn more about the water cycle with their very favorite toy- LEGO®. LEGO® is such a great manipulative and allows children the opportunity to learn a variety on concepts in a hands-on way! We hope this activity allows your little ones to better understand what may seem like a typically hard topic as they learn through their very own LEGO® play!


  • Bulk LEGO® pieces in a variety of colors (we recommend utilizing bricks that are yellow, green, blue, and white for the majority of your build.)
  • Baseplate
  • Pen, pencil, or crayon
  • Scrap paper
  • Scissors

Set Up:

  1. As always, gather all the supplies necessary to complete this S.T.E.A.M activity!
  2. Before getting started with your crew, we recommend reviewing our brief explanation of the water cycle found at the bottom of this blog post under the section titled "Context".
  3. Once you’ve read through that and feel confident in your ability to facilitate play and learning around this topic grab your kiddos and get started!

    Let's Play:

    Explain the water cycle step by step allowing for breaks to build the topics as you are discussing and learning them.


    Step 1: Precipitation

    1. As you explain this step encourage your child to build a cloud out of their LEGO® on the left side of their baseplate.
    2. Then have them choose one of the forms of precipitation (rain, sleet, or snow) and add that too.
    3. Last instruct them to build some land beneath their cloud.

    Step 2: Evaporation

    1. First, have them add a body of water next to their section of land.
    2. Second, build a sun over the section of water.
    3. Then, explain what evaporation means and how it works! As you do this, add additional bricks (in the same color your child used to represent water) moving into the air to demonstrate the sun’s heat evaporating water droplets into the atmosphere.
    4. Regardless of the ages of your family, adding in the activity linked in our “Consider This” section may help drive home this principle even more! Plus, who doesn’t love some extra real life, hands-on learning and application?

    Step 3: Condensation

    1. Explain the last step of the water cycle!
    2. Separate from your baseplate build, use some extra bricks (in the same color of your water) to show how they move up and condense (bunch) together. Have your “condensed” creation reflect the cloud on your child’s baseplate so they can tangibly see how the “evaporated” water from lakes and oceans condenses together to form a cloud and the cycle begins again and again!
    3. Cut a small piece of paper, draw an arrow, and add it to your baseplate between the sun and cloud to illustrate this step on your LEGO® Water Cycle Model.

    Step 4: Review

    1. Cut 5 scraps of paper and write the 3 steps of the water cycle each on a separate slip. Draw two separate arrows on the 2 remaining strips of paper.
    2. Have your child “show & tell” their build to you or other family members and use the slips of paper to label each step as they go! This is a great way to allow them to immediately recall what they’ve learned and solidify these topics by having to explain it in their own words. And if they need some extra help- no worries! An extra opportunity to fill in some more gaps!

    We hope you enjoy this activity as much as we did! Check out our "Consider this" section for ways to extend this activity or adapt it to different learning levels!


    Consider this:

    • Completing a K.W.L "Know, Want to Know, and Learn" chart prior to beginning your activity about graphing.
    • If developmentally appropriate, involving extended discussion about additional terms related to the water cycle like run-off, transpiration, collection, etc.
    • Finding an educational book or episode that teaches about the water cycle to introduce the topic and give context at the beginning of the activity, or to solidly principles learned at the end. You can find a brief list of examples at end of this email!
    • Adding extra opportunities for building and creativity by having your crew build animals or plant life on the land and water.
    • Adding in a rainbow to your build and discussing how they are formed as it relates to the water cycle.
    • Prior to building your water cycle model and discussing each step, having your kiddo choose a geographic location (whether that be a specific state, habitat, country, etc.) that they would like to apply to this activity. Allow that location of choice to influence their choices in regards to what animals, plant life, and type of precipitation they choose to highlight in their model. (This idea can help concepts build on one another if your kiddo has just recently learned about the weather, different countries, or habitats in school. It also gives them an opportunity to do a little research to learn about such topics if they are familiar with the overall concept, but unsure of the actual details.)
    • Adding in this real life example of Evaporation:
      • Set a pot of water on the stove to boil. Narrate the process as it's happening to help your children physically see an example of evaporation.
      • For example: What's the fog above that pot?/ Do you see all that fog above the pot of water? The water is changing from a liquid to a gas, creating the fog- this is called evaporation.
    • Adding in this real life example of Condensation 
      • On a warm sunny day set a glass of cold water outside. If this is not available due to weather, consider doing the same thing but in the bathroom while someone is taking a hot shower.
      • After a few hours of leaving the cup outside OR when you're done with your shower lead a discussion about condensation with your kiddos.
      • For example: Notice the water droplets on the outside of the cup? Do you see the water droplets dripping down the mirror? This is condensation. It happens when water droplets in the air form and condense together.
    • Discussing the filtering of water in nature and what contributes to clean and dirty water around the globe. Regardless of age we recommend that after this lesson you highlight that water is a finite resource. Although this can be hard to explain, this principle is one of the early introductions to environmental science and teaches children why it's important to take care of the Earth we live on. (The book, The Water Princess, can help prompt this discussion.)

    Context for Adults:

    The water cycle includes three main parts: Precipitation, Evaporation & Condensation. Today we will be focusing on each of those points in addition to sharing a few extra things you can do to extend this activity for your munchkins!

    1. Clouds produce precipitation in a variety of forms (rain, sleet, or snow). These different forms of precipitation fall from the sky to Earth and then drain into Earth’s masses of water. (lakes, rivers, creeks, oceans, etc.).
    2. As the sun heats the atmosphere (air) around us, droplets from those bodies of water begin to evaporate into the air (or atmosphere).
    3. Once the droplets reach the upper layers of the atmosphere, they condense together to form clouds, and the cycle continues.


    Book List and Video Resources:

    • Did a Dinosaur Drink this Water?
    • Drop
    • Down Comes the Rain
    • A Drop Around the World
    • The Water Princess
    • The Water Cycle at Work
    • The Magic School Bus: Wet All Over (Both in book and video form)
    • Bill Nye The Science Guy: The Water Cycle Video
    • Sid the Science Kid, Encyclopedia of Discovery: The Water Cycle (T.V Episode)

    We can't wait to see everything that you do with this activity! Share your experiences on social media, tag us, and use the hashtag #LEGOsteamwithBAM so we can see all the fun that you had!

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