Water Strider Science Experiment – Insect STEM Activity for Kids
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Have you ever heard of a water strider? It’s an insect that can walk on water—and it’s not magic, it’s science! In this fun and educational insect science activity, we explore the unique abilities of water striders and challenge kids to create their own floating insect models. This hands-on project is perfect for learning about surface tension, insect anatomy, and simple STEM engineering!
What Is a Water Strider?
Water striders, part of the insect family Gerridae, are sometimes called Jesus bugs because of their fascinating ability to walk or glide across the surface of water.
So how do they do it?
It comes down to two key things:
- Surface tension – Water molecules are attracted to each other and form a type of skin at the surface. This “skin” is strong enough to support small, lightweight insects.
- Specialized legs – Water striders have long, thin legs covered in tiny water-repellent hairs that trap air. This keeps their bodies from getting wet and helps them glide with ease.
This natural adaptation is a perfect introduction to physics in nature!
Make Your Own Water Strider (STEM Engineering Challenge)
You won’t be able to exactly replicate nature, but you can experiment with buoyancy and balance by building your own paper insects and seeing which designs float best!
Supplies:
- Colored index cards or cardstock
- Scissors
- Optional: markers, googly eyes, ruler
- Bowl or tray of water
Instructions:
- Fold your card in half to make it sturdier.
- Cut out a simple insect shape with long legs and antennae.
- Experiment with different leg shapes—try wide, triangular bases vs. thin legs.
- Carefully place your paper insect on the surface of the water.
- Observe: Does it float? Does it sink? What helps it stay up?
What Kids Learn from This Activity
- Surface tension basics
- Why water doesn’t “grab” the bug’s legs
- How shape and design affect flotation
- Engineering thinking: testing, observing, adjusting
Ask questions like:
- What shape floats the longest?
- What happens when we add more weight?
- Can we design one with “hairs” like the real bug?
Add a Creative Twist
- Let kids decorate their water striders with eyes, stripes, or insect anatomy.
- Use a stopwatch and race the floating bugs—how long can they stay up?
- Create a simple chart to record which designs float best.
STEM Extensions
- Oil vs. Water Test: Drip oil or soap in the water to break the surface tension and watch what happens!
- Surface Tension Drop Test: Place water droplets on a penny to see how many stack before spilling.
- Nature Walk Connection: Go pond dipping or creek exploring to see if you can find real water striders in your area.
Book Pairing
Pair this activity with a nature book like Ultimate Bugopedia for a deep dive into insect life. You can also use your own insect field guide to compare bug adaptations.
Perfect for:
- Spring science units
- Insect-themed weeks
- Outdoor classroom or homeschool STEM
- Rainy day indoor science fun
See More of Our Insect Science Ideas:
Paper Insect Display
Insect Hotel
Pitfall Insect Trap
This Water Strider Science Activity is a great way to blend observation, hands-on creation, and real-world science. It’s easy to set up, super affordable, and kids will be amazed at how much they can learn from the tiniest bugs in nature!
