Posted by on Oct 30, 2013 in Activities for Halloween, Bugs, Halloween, Science Activities | 1 comment

With Halloween just days away, I thought it would be fun for the boys to conduct  a couple of science experiments starring… GUMMY WORMS!

Growing Gummy Worms


  • Gummy Worms
  • Container of Water

Conducting the Experiment:

When I asked M to predict what he thought would happen to the gummy worms if we soaked them in water for a few hours, he confidently replied, “I think they’ll get bigger”. I’m pretty sure his response was related to the growing dinosaurs we purchased from the dollar store a while back. In any event, we performed the experiment to see if M’s hypothesis was correct.

I put a glass container of water on the table, along with a few gummy worms, and had the boys drop the worms into the water.

Gummy Worm Science 2  Gummy Worm Science 1

They kept fishing the worms out of the water and dropping them back in again…

Gummy Worm Science 7  Gummy Worm Science 6

Gummy Worm Science 4  Gummy Worm Science 3

We left them in the water for several hours, then checked on them again when M came home from preschool. The boys noticed right away that there was a definite change in the size and texture of the worms. M’s prediction was correct; the worms had grown bigger, and they felt extra soft and squishy!  The boys couldn’t resist trying a bite of the jumbo worms, although they quickly decided they weren’t nearly as tasty!

Gummy Worm Science 27  Gummy Worm Science

Gummy Worm Science 29  Gummy Worm Science 30

The Science Behind The Experiment:

Gummy worms are made up of sugar, gelatin, and flavouring/colours (usually artificial). As the gummies sit in the water,  the sugar begins to dissolve; meanwhile, the gelatin absorbs the water like a sponge, making the gummy worms grow and swell.

Extension Activity:

*Try leaving the gummy worms in the water for different lengths of time *Try submerging the gummy worms in different liquids (ie. vinegar, apple juice, baking soda mixture, soda pop) for the same amount of time, and see what happens!

Wriggly Worms

I got this idea from a great blog called The Kitchen Pantry Scientist. This blog is full of fun and simple science experiments you can do with your kids, using  ingredients you likely already have on hand in your pantry.


  • Gummy Worms
  • Water
  • Scissors
  • Baking Soda
  • Vinegar

Conducting the Experiment

First, I cut the gummy worms lengthwise into quarters (making 4 skinny worms per one gummy worm). Next, I had M mix a few tablespoons of baking soda in a cup of water, while B dropped the gummy worms inside.

Gummy Worm Science 10  Gummy Worm Science 12

We let the gummy worms sit in the baking soda mixture for 15-20 minutes (it’s recommended to let them sit between 15-30 min.).

Gummy Worm Science 13

Then M fished the worms out of the baking soda mixture with a fork, and dropped them into a glass of vinegar.

Gummy Worm Science 18  Gummy Worm Science 14

When the gummy worms became submerged in the vinegar, they immediately sprang to life and began to wriggle and squirm!

Gummy Worm Science 16  Gummy Worm Science 26

The Science Behind The Experiment:

The gummy worms begin to wriggle and squirm when the baking soda (a base) comes in contact with vinegar (an acid) producing a chemical reaction (carbon dioxide gas bubbles).


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Thanks for stopping by!