SAME APPARATUS - TOTALLY DIFFERENT EXPERIENCE

I have been asked how long I keep the same apparatus in the sensory table.  I usually keep it in the table one week.  Every once in awhile I keep the same apparatus in the table for two weeks, but the second week, I exchange the medium in the table to create a totally new and different experience.  One of the apparatus I keep for two weeks is the Water Ramp from last week's post.

The new medium is oobleck, a solution of cornstarch and water.

Can you see the difference?  It is the same apparatus, but oobleck fosters a much different experience.

When mixed together, the solution of cornstarch and water has unique properties.  If you squeeze it, it is like a solid.  If you let it go, it melts or pours like a liquid.  In scientific terminology it is called a non-Newtonian fluid that changes from a liquid to a solid state when stress is applied.  In other words, it has properties of both a solid and a liquid.  (3M has made a lot of money off a substance with such properties with their post-it notes and removable hooks.)  I have no recipe for the ratio of cornstarch to water; I mix until I get the consistency I want.  If there is too little water, the mixture is too hard.  If there is too much water, it is too runny.

One of the original ideas for building the water ramp with patterned dowels was to have children experience how water gets dispersed as it flows down a ramp with obstacles.  That worked, but by using the cornstarch solution, which flows more slowly, the dispersal pattern is easier for the children to see.

That is true even when it dries.

The substance can form a ball and stick together.

The substance can ooze.

You can catch with your hand when it drips.

With the right utensils, it feels more like cooking.

Here are two sequential videos that illustrate nicely the melding of an apparatus, the medium, and the children's imagination.  In the first one, two boys are collecting the oobleck in bowls.  The one kneeling is scraping from underneath the tray and the ramp.  That exemplifies nicely how a child can find spaces that are not readily apparent(See axiom #2 in the right hand column).  Also, notice where he has his bowl.  It is suspended between the table and the ramp so it is off the bottom of the table.  That frees up his hands and allows him to scoop the oobleck using one hand to scrape and one hand to counterbalance the force needed to scrape.  If you listen to him talk about putting the solution into "our bowls," notice how his voice matches the cadence of working with the obleck.  Slow and deliberate with a lot of effort.  The other child is moving around the table saying we are collecting all the "hot lava."  That is the clue to the purpose of their activity. He first scrapes on one end and then from under the ramp before dropping it in his bowl.   Watch and listen.



In the second video, the two boys have filled their bowls.  That was no easy task because it is hard to scrape the obleck.  You remember that it turns to a solid under stress: the scraping.  It took time and it took persistence.  As the video starts, they are poised to pour the "hot lava." One of the boys says: "Come on, let's do it." They pour the contents of the bowls down the ramp. After pouring, the other boy says: "Get shovels.  Catch it."  They proceed to  retrieve their shovels and try to catch the "hot lava" flowing down the ramp.  As they do that, they narrate what they are doing and what is happening.  Watch and listen.

Pouring and Catching the Hot Lava from Thomas Bedard on Vimeo.

With the ramp and the oobleck, these two boys have used their imagination to recreated lava flowing down the side of a mountain.  In other words, the three elements---apparatus, material and imagination---combine so these boys are foreshadowing the kind of modeling adult engineers and scientists do all the time in real life.  Now that is impressive work for two young engineers and scientists.