Hydrodynamic Jellyfish
Explore hands-on physics with the Magical Jellyfish Bottle, a simple yet fascinating science activity that demonstrates pressure, buoyancy, and density in action. When placed inside a sealed, water-filled bottle, the flexible jellyfish responds to gentle squeezing by sinking, floating, and spinning—bringing abstract science concepts to life.
• Demonstrates buoyancy and pressure through hands-on experimentation
• Helps children observe cause and effect as water pressure changes
• Encourages early STEM and physics exploration in a visual, engaging way
• Perfect for science centers, calm-down spaces, and curiosity stations
• Small, lightweight jellyfish responds easily to gentle pressure
• Great for individual discovery or guided classroom demonstrations
To use, place the jellyfish inside a clear plastic bottle filled with clean water and secure the lid tightly. When the bottle is gently squeezed, increased pressure causes the jellyfish to sink. Releasing the pressure allows it to rise again. Children can experiment with different squeezing techniques to observe how motion and buoyancy change.
The jellyfish body measures approximately 0.75" x 1" with 1" long tentacles, making it easy to observe movement without overwhelming the bottle. Colors vary (blue, red, or white).
A compact, affordable science tool that turns a simple bottle into an engaging lesson on hydrodynamics, perfect for sparking curiosity and scientific thinking.
- Ages 5 yrs. +
- Bottle not included
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For the past 70 years, each product is selected based on our knowledge of early childhood education combined with research insights, observations of young children in the classroom, and feedback from our customers
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