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Okay, we admit it. These are kind of juvenile, and at first glance, they do very little for your brain cells. But these are Brainbows - colorful chemistry wonders that are a major step up from the old-school kind!

For starters, they grow up to 100 times their original size when immersed in water, and (most awesome of all) can be reused repeatedly. They are designed for bouncing, throwing, smashing, spitting from a straw, and other delightfully immature activities we have yet to think of.

Brainbows™ need 2-3 hours completely submerged in water to reach their full multi-colored potential as marble-sized spheres that are perfect for tossing, smashing, and anything else your child wonder can think of.

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The Idea

Multi-colored, marble-sized spheres that grow in water.

The Brains

Inspires creative thinking and scientific reasoning.

The A-Ha

Submerge in water for several hours and watch them grow.

Brain Health Expert Says

Introduces users to the extraordinary range of properties of polymeric materials, and facilitates exploration. A fun example of chemistry principles.

The Brain Coach Says

The Brainbows are not only beautiful but they are also awesome ammunition for the da Vinci Catapult and Trebuchet. You might even fling one over the Brainbow!

Let these little guys take you somewhere over the Brainbow.

Product Details

Brain Category
Recommended Age4+
# of Players1+

Customer Reviews



My daughter saw these in the store in a HUGE bowl just waiting for hands to dive in, which they did! So we bought some and took them home. The guy in the store told us that the amount in the tube was what they had on display which was ALOT, so we just poured about an inch worth out of the tube into a mixing size bowl covered them in water and waited. After about 4/5 hours they were ready, they are super fun to stick your hand in and just mess with. As long as these things are in the bowl they kind of feed off each other, we had them out for 2 weeks and didn't have to add any water or do anything. Kind of had me wondering how sanitary they were after a while with hands going in and out! Anyway, time to shrink them back down to size and put them back in the tube with the rest. So i rinsed them in a sieve and laid them out on a few pieces of paper towel, 4 days later not much was happening! So i realized, these things have to be not touching, yes you have to make sure each one isn't touching another one, it was a bit painstaking and i probably should have just thrown them out, but i was unsure how environmentally friendly they were so i separated them all so they could dry out. I also placed the paper towels that they were on on top of a cooling rack so that air could get in underneath too and the paper could dry out, like this it took about 48 hours to get them back to their original state. So def bare this in mind if you plan on using a lot. It takes up some room having them all spread out like that to dry! All in all, fun and entertaining, aside from the clean up. I would recommend.

are they safe?


they are super fun and grow quite quickly, but it is not clear if they can end up in the garbage disposal, or if they are dangerous to pets and animals.