By Jennifer La Lima
That
was one of the many lessons that Martin Avenue third-graders in the North
Bellmore District learned during a recent class on air pressure. Wide-eyed
and amazed, the children listened as teacher Tiffany Joosten explained further.
We are not crushed by the great amount of air pressure above us and around us because there is air inside of us, pressing out and upward, Joosten said.
With balloons and cheeks full of air, the students got a chance to see for
themselves just how powerful this thing called air pressure is.
Joosten believes in making education fun. She said, "I feel that the kids learn so much more when they have the chance to figure out the answers themselves. By using hands-on lessons, the kids are enjoying what they are doing while they are learning."
For their first experiment, students learned a little bit about traveling on air. The class placed their notebooks on top of a flat balloon, and then blew into their balloons. For most students, the air pressure moved the books. They then attempted to lift other objects by blowing up a balloon beneath them.
Each experiment was followed by a discussion in Joosten's class. Student
Chris Cleary said, "Air pressure can really hold up a lot of books."
Students were creative in finding objects to move by blowing up their
balloons. They were able to move a few notebooks, but other items such as
chairs and a bucket filled with pennies, were too heavy. Joosten explained that a hovercraft travels above the surface of the water by using air to lift itself. The class learned that air is blown under the hull of the boat, similar to the way students lifted notebooks by blowing air into a balloon beneath them.
The second experiment was an inside look into a classic magic trick. How many of us can keep water inside a glass that has been turned upside down?
After a few spills and some wet desks, Joosten's class figured out just what
they could do with a little air pressure.
Joosten gave each student a half-full glass of water, a square piece of
cardboard and a bowl to practice over. Joosten's trust in her students was
apparent in the slightly messy experiment. Classmates took turns flipping over their glasses of water. Soon the room was filled with excited voices as the
children attempted to figure out what was keeping the water inside their upside-down glasses.
Student Kaitlyn McCleneghan carefully placed her cardboard over the top
of the glass and turned it over. She said, "Water can stick to the cardboard
and make a seal. There was also air in the glass, and the air pressure made
the seal stay on the glass."
By this time, students were beginning to understand how air pressure
works. Many students understood that a seal was made when they took their
hand away from the cardboard on their upside-down glass. The difference between
the air pressure inside and outside the glass was enough to support the water.
Joosten ended the lesson with an experiment in buoyancy. Using pieces of
clay, each student tried to create a shape that would float on water. One by
one, students found that a clay boat could float more than clay formed into
other shapes. The class was given 15 minutes to construct a strong boat to hold the most marbles. Students learned that the weight of the boat is equal to
the amount of water it displaces.
Joosten said, "A ball of clay weighs the same as a boat made out of the
same clay, yet one sinks and the other floats. It all depends on the shape
of the object, not the weight."
Kaitlyn McCleneghan and Kristen Sforza were both surprised that they could learn so much from these experiments. They agreed that the lessons were also fun.
Comments about the story? JLaLima@liherald.com or (516) 569-4000 ext. 234
