Moving Water – Siphoning

We all know about Jack and Jill and their unfortunate experience.  Wouldn’t it have been nice if they’d just had running water? 

When exploring water with little ones, I like to talk a bit about moving water from one place to another. (Sometimes with a sensory table prepped like this.)  How would we move it from one jar to another?  How do tools of different sizes and construction carry the water differently?  Exploring questions like these invite children to investigate simple tools, concepts like volume, and properties of water (plus, it’s easy to work in a little nursery rhyme discussion).

After a bit of exploring water with tools like scoops, sponges, measuring cups, basters, and eye droppers, I like to do a little siphoning demonstration as well.  Here’s how it goes:

Start with two clear containers, one with water and one without.  The container with the water needs to be elevated a bit higher than the container it will be emptying into.

Next, add a little color to make the water more visible.  (Just watching the coloring swirl and disperse is a fun science observation in itself!)

 Connect clear tubing (found at the hardware store) to a baster.  The section of the tubing is cut just a bit longer than the baster.

Put the tube in the water and squeeze the baster to get all the air out of the tube.  (The kids get as much mileage out of this bubbling step as possible!)

Release the bulb of the baster to start sucking the water through the tube, and simultaneously pull the baster out of the tube to allow the water to run into the empty container.  It may take a little practice and some tweaking before you’re ready to do this activity with the kiddos, but once you do, be ready to do it again and again! 

Siphoning may be a complicated process for young children to fully understand, but I do like to talk to the children about how the baster sucks the air out of the tube.  Without the air there, the drops of water all like to stick together.  That’s why they appear to defy gravity,  moving up and over the edge of the first container and flowing continuously into the other container.

In reality, it’s because of gravity — not in spite of it — that siphons work.  Read more about it here.

I like to put my finger over the opening of the tube, to stop the water from flowing.  Then I start it up again simply by removing my finger from the opening.  I talk to the kids about how the water in our homes is in pipes, even when we aren’t using it.  When we turn on our faucets, it’s like the tube opening up again!

Of course, we have to explore a little plumbing after a discussion like this!  When the children check out the pipes and tubing under the sink, it’s a lightbulb moment as they realize that the water doesn’t just magically appear!

Stay tuned for a full unit on water coming soon! 

What are your favorite water exploration activities?



Filed under Learning through Play and Experience, Uncategorized

8 Responses to Moving Water – Siphoning

  1. Siphons are cool, but I don’t think that the toddler in the picture appreciates it at all, other than that they get to play with water and turkey basters :) Some adults barely appreciate a siphon.

    You don’t need the baster. You can coil a tube within a bucket to fill it with water, then seal the end with a thumb while you pull that end out to the lower bucket.

    If everything is transparent you can put two buckets side by side at the same level and start the siphon from one bucket into the other. Some water will transfer but not all. When does it stop and why? How can they reverse the siphon once it stops? Some bubbles in the siphon tube are ok, but too much will make it stop working … why? Those are good investigations for the kids to see if they really understand (99% sure toddlers won’t, but most adults won’t know the answers to those questions either even if they claim to know how a siphon works).

    • notjustcute

      LOL! Good call. I wouldn’t recommend this activity for toddlers. I usually do it with older preschoolers and school-agers, but as I was doing it with my boys, it was the youngest who managed to sneak into the pictures. The other hands in the pictures belong to me and my older two. Apparently the youngest found it interesting enough to stick around– though he does tell people he’s six. :0) Great investigation questions — they take a demonstration and turn it into a real experiment. I also like your other siphon starter technique. I’ll have to try that one out. Back where I grew up, a lot of the farmers use siphon tubes to water the crops in their fields, so it’s always been a fascinating concept for me and a lot of kids around there….though I’ve never been very good at setting tubes! :0) As for my current home, we get some good application experience every time we clean out the fish tank!

  2. msladydeborah

    Reading this post just reminded me that I forgot to add a baster to my sensory materials for the week. We are working on motion and a siphon is on my plan.

  3. Pingback: Preschool Study Unit: Water | Not Just Cute

  4. Very cool, thank-you for this. I’m a very old kid (pushing 60) and needed a reminder as to how this works! (Am trying to get water out of a full water barrel.) I think I’ll be using my mouth rather than a baster, hope I don’t get a taste.
    P.S. Does water surface tension have anything to do with this? Can you recommend a good basic science site that deals with this on a slightly more theoretical level? It’s fascinating!

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