Science Experiments: Osmosis, Part One, The Worms

My kids LOVE science experiments. For the most part, I enjoy them as well.  They are, unfortunately, the first part of our homeschool plan to get cut when things get crazy busy.  This year, I’m trying to make sure we get at least one in every week.  The topic is unimportant, as long as we practice the observation and journaling of the process.

Osmosis, Part One: The Worms

Osmosis is the movement of water molecules across a selectively-permeable membrane down a water potential gradient.[1] More specifically, it is the movement of water across a selectively permeable membrane from an area of high water potential (low solute concentration) to an area of low water potential (high solute concentration). Less specifically, it is when water moves. –Wikipedia

The unofficial definition we used over lunch while admiring our worms? Osmosis is when water moves to dryer areas.


Pie pan, dish, or bowl


Gummy Worms (or bears… but worms were available)


Paper and pencil


1. Measure gummy worm (bear) and draw a picture of the ‘before’.


2. Put gummy worm or bear in the water. Mark the time on your paper.


3. Pass the time by eating some gummies.


4. At regular intervals, enjoy observing your worms.


5. DO NOT try to move the worms… they break… and little people cry and start thinking they will “never be a scientist!” **oh my gosh the drama**


6. After 24 hours, mark the time and draw a picture of your ‘new’ gummies.  If you can, take new measurements.



Mama Smiles did this experiment with her littles! Check it out here!

Here is a great pdf worksheet of the experiment from with directions for making a worm growth chart!