A few weeks ago, we were erupting our newest volcano, the third we've manufactured on my watch. (If you're interested, I've written posts on all 3 --
here,
here, and
here. The second link is probably the best tutorial, although the third one shows an even more child-centered approach).
After going through the whole process of adding baking soda, vinegar, orange paint (for a realistic color) and dish soap (to create a foamy, less explosive eruption) a couple of times, we decided to try the experiment of stopping up the vent with a wine bottle cork. We've tried this before, but have never succeeded it getting it to "blast off." This time, however, I really went to town with extra baking soda and vinegar, foregoing the dish soap and paint. As you would expect, the eruption began instantly and I hurried to jam the cork into the top, telling everyone to back up a few steps because, "If it does blow everyone nearby is probably going to get wet."
Then we waited.
And waited.
And waited.
All the while we chatted about what we thought was going on inside the volcano. Some of us bravely stepped closer to report that tiny bubbles were emerging from around the cork. I thought that might mean the seal wasn't tight enough, but the kids took it as evidence that she was about to blow.
There were a lot of other things going on in the outdoor classroom, but most of the kids were gathered around, anticipating. In fact, the anticipation became too much for a couple of the younger children who began to cry. Parent-teachers picked them up with the idea of carrying them away, I think, but that never happened as, it seemed, no one wanted to miss the moment.
I lead us in a count-down, starting with 20. Nothing. I lead us in another countdown. Still nothing.
Then suddenly, just as the kids were starting to lose their focus, just as I was about to pull the cork out so we could at least witness the pop and spray of the built-up pressure being released, just as I figured this was going to be yet another dud . . . Pow!
No one saw where that cork went. Everyone within about a 10 foot radius had orange freckles. The cedar branches 8-feet over our heads rained vinegary droplets down upon us. There was a moment of stunned silence, then cheering and laughter. "Do it again!"
The second time, we saw the cork come down over by the concrete slide, some 25-feet away.
So we tried it a third time, but since we were at the end of our day and parents were arriving to pick up their kids, we carefully carried the corked volcano up to the top of the hill where we hold our closing circle, the idea being that it would blast off as we were reading our story. This time nothing happened. As the kids began to clear out, one of them wandered over by the volcano and pushed the cork all the way into the bottle, releasing what little pressure that had built up and, sadly, permanently crippling the volcano. (I've learned from experience that once there are chunky things in there, the volcano will never again erupt as wonderfully as before.)
The next time we got together we went right work building a new volcano, a three day process. We pretty much followed the regular procedure, starting with a 2-liter soda bottle, creating a masking tape frame, then laying down a couple layers of paper mache. Instead of painting it, however, as we've done in the past, we decided to make it even more "realistic" by covering it in a thick layer of a dough we made in our sensory table using flour, coffee grounds, salt and water. We also added some sticks, wood chips, rocks, and a plastic frog. Then we set it in the sun to "bake" for a day.
I think it looks awesome, although it weighs a ton! It erupts just fine and the orange lava looks dramatic against its mud flanks. And yes, it does shoot corks!
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WOAH! I LOVE IT!!! :) I feel like I'm there watching through your writing. Bravo!
ReplyDeleteI'm a 5/6 teacher in Australia and I teach a lot of science in my classes... if you really want to impress your students... dry ice and water (and for bibles a little dishwashing liquid) are fantastic!
ReplyDeleteof course there is the isue of safety but if you fill the soda bottle it should be fine... and it will go off every time without destroying your volcano (but don't use a cork)
Rebecca