Digestion Model

Today 5th Graders Digested Food 

Before Lunch!

First,   we explored what spit does to starch.  It has an amazing power to break starch into sugar!   Starch is actually chains of sugar linked, and salvia has the power to break those connections.   We tested our spit in a test tubes of starch.  Initially the iodine turns the solution black (indicating starch is present.)  By the end, the iodine is brown!  That means our very own saliva broke down all of the starch into sugar!  Sweet!

Starch mixed with saliva over time.   The black color indicates starch.  Notice by #6 all the starch has been turned into sugar (evidenced by the brown color.)

After exploring the incredible super power of our saliva to make sugar from starch, we built an active model of the digestion system.

First we cut food with our "teeth"- knife.  We found that teeth really have to work hard to get food into tiny pieces!

After we thoroughly chewed our food, down the "esophagus" it went to our "stomach" jar.

"Stomach Acid" started breaking down the food into a "slushy" scientists like to call chyme.

Our filter paper acted as the small intestine's villi and absorbed the "nutrients" from the food.  

All that was left is a bunch of waste, and we all know what happens to that!

You can sing along with Body Machine by School House Rock or check out a digestive system game.

Check out this game designed by Kino Creative for "Love your Gut" week!  You are a sandwich and must get through the digestive system.  Be sure to read the directions carefully and use the arrow keys to play.  I can make it all the way through, can you?

http://www.loveyourgut.com/games/gut_week_game.php

What's the Matter?

Third Graders learned about matter today!

We talked about solids, liquids, gases and plasmas. 
We also looked at ways to determine whether something was a solid, liquid, or gas by looking at the shape and volume of H2O in solid, liquid and gas form.

Which one contains a solid? Liquid? Gas?

We also explored ways to change matter from one state to another.  Sometimes we had to add energy to change states (using heat to melt a solid ice cube into liquid water), and somtimes we had to take away energy (cooling down water vapor in our balloon and changing it into liquid water.)

A little bit of water in the bottle is heated with hot water and turns to vapor to fill the balloon

The vapor condenses into water and falls out the the balloon when energy is taken away with cold water.

We also looked at creating a new form of matter using the chemical reaction of baking soda (solid) and vinegar (liquid) to create carbon dioxide gas in the bubbles. Don't forget your goggles!

Lastly we looked at an interesting compound that goes directly from a solid to a gas, skipping the liquid stage (the fancy science word for this is sublimation!)

This compound is Carbon dioxide!  The same gas you breath out every day as well as the one you made with baking soda and vinegar!

Carbon dioxide as a solid is known as "dry ice" because it skips the liquid stage and turns into gas.  To become a solid from a gas, it has to be really cold with a lot of energy being removed!  We decide to go the other way and warmed up the solid in water and were able to trap the gas inside bubbles!

Try sorting items into their correct state using the link to the game below!

http://www.spaceweathercenter.org/interactives/matterSorter.html

or check out this link to a matter song by Peter Weatherall.

http://www.kidsinglish.com/newspeak/video_clips/simple-sci-samples-wmv/matter-song-samp-wmv.wmv

We finally figured out "What's the Matter?"  It was a solid, liquid, gas or plasma!

Model Lung

5th Grade learned all about the respiratory system today, by building their very own model lung!

With a bottle, balloon, straw, glove, and clay students were able to demonstration how the air pressure difference created by the diaphragm contracting and expanding actually causes the lungs to inflate!   It is all about air pressure and that amazing diaphragm muscle!

 Below is an exaggerated diagram to show the difference in air pressure.

Notice that when the lungs inhale their are more particles outside because the diaphragm moves down spreading out the particles inside. Air "wants" to come through the trachea to even out the air pressure.  The opposite happens when the diaphragm relaxes in an upside-down u shape. (pushing the air particles close together.) Check out this animation from OregonStateVetMed on You Tube of what happens in your body.

Now, check out the one we made!

Something to think about:  How is the respiratory system connected to the circulatory system?

Weathering, Erosion, Deposition

Weathering and Erosion with 4th Grade today!


Weathering is the breaking down of rock into smaller pieces (sediment).  Physical weathering occurs when the forces of nature break down rocks without chemically altering the original rock (we smashed one with a hammer today!)   



We took sugar cubes and physically weathered them today by shaking 6 of them in a cup and removing one every hundred shakes.  Wow did the shape change!  We were left with some rather sweet sediment!

Sweet weathered "rocks" changed shape
and size as weathering time increased!

Chemical weathering alters the composition with a chemical reaction making the substance become something different.  Think rusty iron, or acid rain and limestone. 

Then, we chemically weathered "limestone" (Tums tablets) with "acid rain" (vinegar) while comparing the weathering rate of still water and moving water (courtesy of eye dropper squirting!)

Erosion is the picking up or physical removable of rock particles by an agent (wind, water, glaciers, even us!)  Erosion moves sediment from one place to another.  Next time you kick a rock you are an agent of erosion.  Secret agent (of erosion) name "Rock Kicker."

 Deposition is the process of dropping off sediments in a new location.  Every time we go to the beach we deposit sand in our car, garage, front yard, kitchen....

Our last experiment showed the whole process!  We weathered a line of Tums tablets by squirting water down a plastic tub on them.  The water broke down the tablets (weathering) and carried the sediment (erosion) and deposited it in the cracks of the tub and the bottom (deposition.)  Wow, Tums really taught us a lot about science with the bonus classroom "air freshener" that smelled rather fruity!

Weathering, eroding, and depositing "limestone"-Tums

We even used motions that represented weathering, erosion, and deposition.  Perhaps it will become a new dance craze! 

Here is a video from the studyjams at scholastic.com  with some good content about weathering and erosion.  What kind of super hero would deposition be?

http://studyjams.scholastic.com/studyjams/jams/science/rocks-minerals-landforms/weathering-and-erosion.htm

Circulatory System Lab

After showing students a great video, courtesy of They Might be Giants called "The Blood Mobile", the classroom becomes a  working model of the circulatory system.  Students belong to 5 different groups: heart chambers, valves, lungs, muscles, and blood cells.  The room has" blood vessels"  (blue and red tape) to show the path the blood cells must follow.

The students who are heart chambers (left and right atrium and ventricle) have balloon pumps and the pump the cells through.  The student valves put their arm across the path way and raise their arm to let blood cells pass.  All chambers and valves must say their name out loud to each blood cell.

Blood cell students are given an oxygen molecule and start on the red tape at the front of the room. They are pumped through the left atrium, let through the mitral valve, pumped through the left ventricle, and let through the aortic valve.  Then students go to the muscle where they give their oxygen to the student muscles (so they can burn fuel) and are given carbon dioxide.  They then travel the oxygen poor path (blue) to the right side of the heart where they are pumped through to the lungs.  When they arrive at the lung, they give their carbon dioxide (to breath out) to the student lungs and are given oxygen.  Then, they circulate again until it is time to switch stations.

Carbon Dioxide (above) and Oxygen (below) molecules easily made from die cut circles, glue and a sharpie.

Here are the links for the lab sheet the students fill out.  As a class we trace through the blood's path on the heart on the inside of the lab sheet with our fingers.
Human Body Lab 2: The Circulatory System
Human Body Lab 2: The Circulatory System Answers