Science Experiments in the Bathtub

4 science experiments for kids

This Wash & Learn collaboration with Bath Activities for Kids focuses on SCIENCE!

wash & learn: science bath time for kids

For our bath time we focused on the science concept of surface tension and did several experiments in the bathtub that the kids would simply consider play.

My goal isn’t for the kids to learn all the reasons behind what happens at this point, but for them to have first hand experience with lots of hands-on science so that when they do learn about the science behind the experiments in the future, they will have memories of hands-on demonstrations of the science concepts which should make learning the abstract a lot easier!

Science Experiments in the Bathtub

Experiment #1: Soap Boats
First we started out by making soap boats.  For this part, we used plastic bread ties with a V shape cut into one edge and dish soap.  To do this experiment, simply place the plastic tie into the water and carefully put a few drops of dishwashing liquid into the “V” shape of the boat.  The boat will zoom ahead through the water.

making soap boats -- surface tension science experiment

Why?  The dishwashing liquid mixed with the water weakens the attraction between the water and the back of the boat.  The pull of the water on the front of the boat is now stronger, so the boat moves forward.

Unfortunately, this experiment can only be done one time because once the dishwashing liquid breaks the surface tension of the water, it does not work again.  This activity is best done at the start of the bath since it will only work the first time.  For repeats, use a small bowl of water that can be filled and dumped in the sink after each soap boat experiment as shown in the video.

Reference: Cool Science Experiments by Hinkler  

Experiment #2: Blow Your Own Bubble Bath
After our soap boat experiment, we squirted lots of extra dish soap into the bath.  We use an all-natural brand.  Following in the tradition of our recent bubble experiments, I gave the kids each a straw and let them blow their own bubble bath.  They had lots of fun with this part!!

blow your own bubble bath blowing bubbles with a straw

Experiment #3: Bubble Snow Globes
The third experiment we did was my favorite, and one I just came up with; I haven’t seen it done anywhere before, though that doesn’t necessarily mean it hasn’t.  We took some of our plastic figurines from the Safari LTD. Penguins Toob we recently received and arranged them in the center of a recycled plastic lid.  (See our Antarctica small world play bath here and enter a giveaway to win your choice of a Safari Toob!!)  Then we covered them with dish soap and a little bit of water.  We used our straws to blow bubbles that totally encompassed the penguins.

bubble snow globes
penguin snow globemake your own snow globe
penguin & chick snow globe
penguin bubbles
blow your own snow globe
snow globe bubbles
bubble bath fun blow a snow globe
penguin baby snow globe
Don’t they look just like snow globes?!?!?   
bubble snow globe fun for kids
Christmas snow globe
snow globe art snow globe with penguin

Experiment #4: Blowing Bubbles in the Tub
After all our fun, the bathtub was just soapy enough the kids could use bubble wands to blow bubbles!  They used their straws some more, too.

bubble wand in the bath tub
bubbles in the tub

For more fun bubble experiments, see:

See our other Wash & Learn and themed bath times:

We hope you enjoyed our science bath!  
Now be sure to click over to 
to see Crystal’s 

Disclosure: Bath time should always be closely supervised by an adult.  The activities involving blowing bubbles with a straw are probably best for ages 4+.  My 3 year old is very good at these activities now but is always closely monitored to ensure she never sucks or inhales through the straw.

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Genny Upton

A former teacher turned stay at home mom to two preschool aged children. Creator (and writer) at In Lieu of Preschool and Parent Teach Play. Currently publishing my first children's picture book!

  • […] Have kids? Here’s a lesson on Surface Tension and how to make bigger bubbles (by altering the solution that makes the surface tension) and science in the bathtub. […]

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