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Steve Spangler Science® Jelly Marbles™ Test Tube

Steve Spangler Science®
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Ages 6+ / Grades 1+
WARNING: CHOKING HAZARD – Small parts. Not for children under 3 years.
You Won’t Believe Your Eyes!

These Jelly Marbles become invisible when submerged in water but grow almost 7 times their size!

Just add water and discover the magic! Place these tiny, solid spheres in water, and in just a little while you will have your own Jelly Marbles that absorbed over 150 times their weight in water. These superabsorbent water marbles are the newest craze around the Spangler Science offices! What starts out as a 3mm pebble, quickly becomes an approximately 20mm ball of jelly! Similar to our Water Jelly Crystals, these water beads absorb a lot of water, plus they maintain their spherical shape when they are done growing. Not only are these superabsorbent marbles fun, they teach a valuable lesson about the power of polymers.

Jelly Marbles are an example of amazing hydrogels
Hydrogels are superabsorbent polymers that are saving the environment. Whether you think they look like water marbles, water beads, or clear spheres, you’ll want to get your hands on these squishy, water-filled Jelly Marbles.

What does it teach?
Like all of our fun and fascinating polymer, or hydrogel, products, these tiny spheres, teach a big lesson in color mixing, light refraction, and the importance these thirsty pebbles can play in maintaining a healthy environment. The possibilities for experimentation are endless when you drop these spheres in water.

Fun For Anytime of the Year, Especially Halloween!
Unsuspecting Trick-or-Treaters will be surprised when they place their hands in a bowl of ooey, gooey “eyeballs”! Perfect for any Halloween party!

Watch Them Grow To the Shape of One of Our Baby Soda Bottles
Your young scientists will be surprised to see that the marbles maintain their spherical shape. Not only do these clear spheres absorb water, but they also absorb color to make them even more interesting!

Instruction Cards Included with 3 Experiments
The Shapes of Hydration
Magnificent Jelly-Marble Magnifier
The Jelly Marble Vanishing Act

What’s Included?
Jelly Marbles™ Polymer 1.16 oz (33 g)
Recommended ages 6+.
Adult supervision required. Do not ingest.

  • Superabsorbent giant growing polymer beads
  • Absorb 150 times their weight in water!
  • Learn about hydrogels and how they’re used to help the environment
  • Color your own marbles and learn about secondary colors!


Brand Name
Steve Spangler Science®
Age / Grade
Ages 6+ / Grades 1+
Assembly Required
Steve Spangler Science

Bundles that Include this item

Steve Spangler Test Tubes Experiment Bundle  

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