Selected activities suggested for grades 3 - 6 at schools hosting a

States of Matter Presentation.

Each activity is referenced to appropriate grade according to the Idaho State Board of Education. A grade level in bold indicates a required topic, with non-bold levels indicating a recommended topic. Relevant chapters in the Houghton Mifflin Science "Discovery Works" series are also referenced. HM 6F3.1 refers to investigation 1 in chapter 3, unit F from the sixth grade text.

AIR HAS WEIGHT

Principle: Density, Buoyancy

Grades: 4, 5

HM 2D4, HM 3C1.1, HM 4B1.2, HM 4B2.1, HM 5C1.1, HM 6C1.1, HM 6C2.1, HM 6F5.3

Inflate two large balloons to about the same size, tape them to opposite ends of a meter stick, and suspend the meter stick by a string tied to the center of the meterstick to form a balloon balance. Adjust the string so that the balloons are balanced. Pop one balloon and the other end of the balance falls, showing that air has weight. Actually what you are showing is that the air in the balloons is slightly more dense than the air around them due to the elastic compression by the latex. The weight of an inflated balloon is always greater than the buoyant force on the balloon from the surrounding air.

ALUMINUM FOIL BOATS

Principle: Density, Buoyancy

Grades: 4, 5

HM 6C1.1, HM 6F5.3

Make boats out of aluminum foil. Float them in a fish tank and see how many marbles they can hold before they sink. This can be a fun competition. Crumple one of the boats up into a ball and it sinks, even though it could float with ten or more marbles. For something to float the buoyant force must equal it's weight. The buoyant force is equal to the weight of the displaced fluid. The more water something displaces, the better it floats. Another way to think of this is in terms of density. The density of the boats can be made very small by having lots of air "inside".

PASCAL'S DIVER

Principle: Density, Buoyancy, Pressure

Grades: 5, 4

HM 4E2.1, HM 6C1.1, HM 6E1.2, HM 6F5.3

Fill a 2 liter pop bottle 4/5 or so full of water. Add an eye dropper or a small bottle, or anything (preferably small & clear) that will just barely float with a small bubble of air inside with the bottom side open. Clay works well to weight things down so that the eye dropper or whatever floats bubble side up. Screw the bottle's cap down so that no air escapes. If you squeeze the bottle, the pressure shrinks the size of the bubble, and the "diver" sinks! Reduce the pressure, and it will rise again! With practice, you can have the diver float at any depth with just the right amount of pressure. The buoyant force on an object is equal to the weight of the fluid it displaces. As the bubble shrinks, less water is displaced, so that it's buoyancy is decreased. You control the buoyant force with your grip on the bottle.

SHRINKING BALLOONS

Principle: Thermal Expansion, Pressure

Grade: 5

HM 3C2.3, HM 4B3.1, HM 6C1.3, HM 6C3.1

Blow up a balloon while holding the open end of a styrofoam cup against it. The balloon should be held tight within the cup when you are done. Cool the cup and balloon in a refrigerator or freezer or on some dry ice. The balloon will shrink because of thermal expansion and will no longer be held tight by the cup. Hot air expands and cool air contracts. The colder air molecules in the balloon move slower and so do not impact the inside of the balloon as hard. The balloon then contracts until enough molecules strike it in a period of time to equal the pressure of the atmosphere and the pressure from the elastic contraction of the balloon.

HOT OR COLD?

Principle: Temperature, Heat

Grades: 5, 3

HM 2B8, HM 3C2.3, HM 4B1.2, HM 5C2.1, HM 6C1.3

Place three plastic tubs side-by-side. In one put very cold water, in another put very hot water (not hot enough to scald!), and in the third tub put luke-warm (body temperature) water. Have students place one hand in the cold water and the other hand in the hot water, and leave them there for at least 10 seconds. Then have them put both of their hands into the warm water. The "hot" hand will feel the water as cold, while the "cold" hand will feel it as hot. This is because our sense of touch is not temperature sensitive, but heat-flow sensitive. If we lose heat to something it feels cold to us, and if we gain heat from something it feels hot to us.

THERMAL CONDUCTION

Principle: Temperature, Heat

Grades: 5, 3

HM 2B9, HM 4B1.2, HM 5C1.1, HM 5C2.1, HM 6C1.3

Place a piece of wood, a metal tray, and a tub of water on a table and leave them there for at least an hour. By then they should all be at the same temperature as the room. Have students place a hand on each object and ask them which feels colder. Our bodies are warmer than room temperature, so we should lose heat to each object. The water conducts heat the best, so it will feel colder, and the wood conducts heat poorly, so it hardly feels cold at all.

AIR TAKES UP SPACE

Principle: Gasses

Grades: 1, 2, 5

HM 2D4, HM 3C1.1, HM 4B1.1, HM 4E1.1, HM 5C1.1, HM 6C1.1

Of the three common states of matter, students are least familiar with gasses. There are several activities that are useful to show that gas, and air specifically, takes up space. Blow up and seal a zip-lock sandwich bag. Have students feel, and squish the trapped air.

Fill a plastic pop bottle with water and seal the top. Poke several large tacks into the bottle, some high, and others low. Remove one of the tacks and almost no water will come out. This is because air must enter the bottle in order for the water to leave. If you take a second tack out, water will stream out the lower hole and air will come in the higher hole as can be seen by a stream of bubbles.

Stick a funnel on the top of a bottle and seal around it with clay. Use a funnel with a small (pencil-sized or so) hole in the spout. Quickly pour water into the bottle. Only a little water should enter the bottle, because it must displace the air to do so. If it is sealed properly, the air cannot escape. If you make a hole in the clay for air to escape, the water will enter the bottle.

Wad up a piece of paper towel and stuff it into the bottom of a clear cup or glass. Invert it and submerge it in water. The towel will not get wet. The water did not enter all the way inside the glass because of the air that is inside.

Stretch the mouth of a balloon over the mouth of a 16 oz plastic pop bottle with the balloon inside the bottle. Try to blow up the balloon. You can't because the air that is inside can't go anywhere. Poke a hole in the bottle and you can blow up the balloon because the air in the bottle can then escape. Seal the hole while the balloon is inflated and it will say that way.

LUNG VOLUME

Principle: Gasses

Grades: 1, 2, 5

HM 2D4, HM 3C1.1, HM 4B1.1, HM 5A2.2, HM 5C1.1, HM 6C1.1

You can measure the volume of air students can have in their lungs with a milk or cider jug, a plastic tube or hose, a pan, and some water. Fill the jug to the top with water. Quickly invert it in a shallow pan filled with about 2" of water. Most of the water will stay in the jug because no air can get inside. Hold the jug upside down with the hole under the water in the pan. Feed one end of the tube into the jug and have a student fill her or his lungs and blow out as much as they can into the tube. The air they blow will displace the water. You can make marks to see who displaces the most water and so has the most lung volume.

GOOP I

Principle: Liquids, Solids

Grades: 1, 2, 5

HM 2D3, HM 3C1.2, HM 4B1.1, HM 5C1.1, HM 6C1.1

In a bowl, slowly mix water into some cornstarch. Add enough water to get the goop to just beyond the "paste" stage. Now play. What you have is a fluid. It flows. It is also an amorphous solid. If you apply a stress (squish it) it acts like a solid, when before it acted like a liquid. When you squish it you force the starch molecules together and they bind to form a solid. Without a stress, the molecules are suspended in the liquid and slide over each other.

GOOP II

Principle: Liquids, Solids

Grades: 1, 2, 5

HM 2D3, HM 3C1.2, HM 4B1.1, HM 5C1.1, HM 6C1.1

Dissolve borax powder into ½ cup of distilled water until no more can be dissolved, and let sit for at least 5 minutes, stirring occasionally. In a plastic cup, mix equal amounts of white glue and distilled water. Add small amounts of the borax liquid to the diluted glue while stirring constantly. Alternate adding borax liquid and stirring until you get a freely flowing goop of uniform consistency. Do not add borax liquid to the point of forming a stringy mass that will not dissolve. Like Goop I, this is an amorphous solid. If instead of working the mixture after the glue gets stringy, you remove the stringy part and rinse it in cold water and then work it into a ball, you can make your own bouncy ball.

BERNOULLI TRICKS

Principle: Bernoulli Effect, Pressure

Grades: 5

HM 1B4, HM 4E2.1, HM 5A2.2, HM 5A3.1, HM 6F5.1

Hook the hose of a Shop-Vac up to the exhaust, so that it blows air instead of sucking. Any vacuum that has such an exhaust will work, as will a hair dryer (with the heat off!), but the bigger the blow, the better. The most spectacular tricks can be performed with a leaf-blower. You may need a nozzle on the end of the hose to get a strong enough air stream. Balance some light balls (ping-pong balls and styrofoam balls are good) on the air stream, and you can do some really neat levitation tricks! Try to see how big a ball you can levitate. In a fluid (like air), pressure is lowest where the fluid is moving the fastest, and the pressure is highest where the fluid is still. The pressure is low within the Shop-Vac air stream, so that balls are actually attracted to the stream. This is called the Bernoulli effect. Airplanes use this to fly. The wings force most of the air over the top, so that the speed of the air is greater over the top of the wing. The resulting pressure difference between the top and bottom of the wing provides the lift. You can even "suck-up" balls if you attach a funnel to the end of your blowing hose, so that it flares out like a horn. The air is moving faster where the funnel is narrow, and that's where the pressure is lowest! Our circulatory and respiration systems in our bodies also rely on this effect, as do many weather phenomena such as tornados and hurricanes.

BERNOULLI FLYER

Principle: Bernoulli Effect, Pressure

Grades: 5

HM 1B4, HM 4E2.1, HM 5A2.2, HM 5A3.1, HM 6F5.1

Place two styrofoam cups bottom-to-botom, and tape together with masking tape. You will need a long (apx. 12") rubber band. Several smaller rubber bands tied together will work just fine. Hold the flyer in front of you and wrap about half of the rubber band tight around the middle of the flyer, counter-clockwise when viewed from the right. Holding the flyer with the wrapped band in one hand and the the end of the band in the other, aim slightly down, pull back and release the flyer. Results: The flyer will spin and rise, and then float slowly downward. Why? As the flyer moves forward and spins, friction between the flyer and the air will cause the air to move faster over the top of the flyer than below the flyer. Air pressure is lowest where the air is moving the fastest, so the flyer gains "lift" due to the differences in the air speeds. This is an example of the "Bernoulli Effect".