More Air Pressure...

Can I lift the newspaper with a yardstick?

Lay a yardstick on a table, with half of the yardstick extending off the table.  Home Depot sells them for 75 cents, but when I told them it was for my class, they donated 10!
cover the ruler with newspaper.  Smooth out and air.

We ask students to make a prediction:  What do they think will happen when we strike the yardstick with our hand in a single whack?  We record their predictions in their notebooks:  Students felt that it would lift and flutter down to the ground (love the descriptive vocabulary). it would be like a kite, the ruler will fly across the room....
We select a student to come up and give it a go.

The newspaper didn't move at all.  The ruler snapped!  

But why?  Well, it is due to the pressure of air on the newspaper.  A yardstick has a small surface area, but the newspaper has a larger area.  At sea level, the air exerts a pressure of about 14 pounds/sq. in.

For a 20inX24in newspaper the surface area is.....?  yep, there's some math in there too!

The weight of air holds a paper down, causing the yardstick to break.

Notebook pages:

 (needs to add the why)

Great links:
http://www.scientificamerican.com/article/bring-science-home-air-pressure-ruler/

Weather

Air Masses

Cold air has a higher pressure, pushes beneath the lower air pressure found in the warm air mass which causes the warm air mass to rise quickly.  As it rises, it becomes colder.  As the air vapor cools, it condenses becoming water droplets. These tiny drops of water are called clouds.  The clouds continue to form and may become dark as they block the sun from reaching the bottom of them.  As the water droplets collide, they join to form larger drops of water that can no longer be held up in the air and fall as rain.

Activity:  To observe the behavior of different temperature masses

Since we can't see air, we will use water which behaves the same way.

Students were given the goal of creating a model to represent the hot and cold masses.  The materials were
2 plastic cups
2 push pins
large clear plastic tub
room temperature water
hot water
cold water (ice)
food coloring

Push pin is inserted into a plastic cup.  Water is poured into cups. Add food coloring. Cups are placed into large clear tub with room temperature water.  Note: the level of water in the cups needs to be higher than the level of water in the tub. Simultaneously remove push pins.  

this student is describing the upward movement of the warm mass

.http://www.coreknowledge.org/mimik/mimik_uploads/lesson_plans/103/METEOROLOGY%20MADNESS.pdf

http://www.mesonet.org/index.php/earthstorm/page/climate_101_workshops - great powerpoints

http://www.thirteen.org/edonline/nttidb/lessons/dn/airdn.html

Layers of the Atmosphere

Atmosphere

Step book for layers of the atmosphere.  We read several selections about the atmosphere.  Students worked in groups to create a page for each layer.

this one is so creative!

http://mjksciteachingideas.com/pdf/LayersMania.pdf

http://www.ck12.org/earth-science/Importance-of-the-Atmosphere/

http://teachertech.rice.edu/Participants/louviere/atmos.html

http://www.msnucleus.org/membership/html/jh/earth/atmosphere/jhatmosphere.pdf

Air Pressure

This activity is slightly modified from the original one I found about air pressure.  

After reading the text we review the concept::   as altitude decreases, air pressure increases.  We do this by discussing the difference between Mt. Everest, and the beach which is at sea level.  To help students see air, we make a model.  The column of air at the top of the mountain is less dense.  There is less pressure.

As our traveler goes down the mountain (altitude decreases) he gains more air pressure.  For this we add a bag of gravel.  The column of air is becoming more dense.  

We continue to add, until he is at sea level (and feeling it)!

This activity helps students understand air pressure using materials to represent the air.  When our discussion is complete, students record their ideas in their notebook.

Weather

Land Breeze Activity -

To help students understand what causes wind, we create a paper plate to compare the slow heating and cooling of the ocean, to the more quickly changing temperatures of land.