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Home » Early Years Science » Waterproof Roof STEM Challenge

Waterproof Roof STEM Challenge

Modified: Feb 22, 2024 · Published: May 22, 2014 by Emma Vanstone · This post may contain affiliate links · 3 Comments

This waterproof roof STEM challenge is a simple but fun activity that even very young children will enjoy. My 3,5 and 7-year-old loved it, especially when it came to making it ‘rain’.

LEGO waterproofing experiment

Before starting, we spent a few minutes talking about what we expected to happen and how we could make the investigation a fair test.

We decided that the roof tiles would be the most waterproof, followed by the sticks and then grass. However, we did discuss that it would depend on how many sticks and how much grass we used and that it would be hard to make the comparison fair.

LEGO HOUSE for a STEM challenge

Materials

LEGO House

Roof materials – we used LEGO tiles, sticks and grass

Water sprayer

Method

Place your chosen roof onto the house and spray water on top. We used a set number of sprays to make it a fair test.

Record any moisture inside the house.

wet roof of a small LEGO house for a science experiment

Results

As predicted, the roof tiles kept the inside of the house dry, the grass let some water in, and the sticks were also waterproof.

lego house

Improvements

To improve the accuracy of this investigation, we decided what we should have done was use grass, sticks, and tiles up to a certain height above the top of the house and keep that constant for all conditions.

Recording the amount of moisture inside the house was difficult. Perhaps if we’d placed paper inside and changed it for each condition, we could have compared the dampness of each piece.

Can you think of any other improvements?

More LEGO science activities

Try one of my 15 Fun ideas for Science with LEGO.

Which is the most waterproof roof

Last Updated on February 22, 2024 by Emma Vanstone

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Safety Notice

Science Sparks ( Wild Sparks Enterprises Ltd ) are not liable for the actions of activity of any person who uses the information in this resource or in any of the suggested further resources. Science Sparks assume no liability with regard to injuries or damage to property that may occur as a result of using the information and carrying out the practical activities contained in this resource or in any of the suggested further resources.

These activities are designed to be carried out by children working with a parent, guardian or other appropriate adult. The adult involved is fully responsible for ensuring that the activities are carried out safely.

Reader Interactions

Comments

  1. Almost Unschoolers

    May 27, 2014 at 2:41 am

    I like the way this got you thinking not only about how to test the different materials, but how to create a fair and accurate test – great problem solving activity!

    Reply
  2. Natalie PlanetSmartyPants

    June 02, 2014 at 2:43 am

    Great idea for an experiment. I was thinking of making a “water level gauge” inside to measure moisture and putting a paper towel square inside to see if it gets wet at all. Thanks for sharing with After School Link Up.

    Reply
  3. Jessica

    April 06, 2015 at 6:47 pm

    I might use water tinted with a little bit of blue food coloring and put a paper towel inside the house. The blue water would show up much better on the paper towel and the results of each type of roof could be compared.

    Reply

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