Science Activities
What is Surface Tension?
Equipment: Coins, drinking glass.
1. Fill the glass with water
2. One by one, drop the coins into the water edgewise.
3. Put in about 25 coins.
Observation: The water will hold many coins before it overflows.
Conclusion: The surface of a liquid will stretch because liquid molecules cling to one another. This is surface tension.
Camouflage Coloring
Equipment: one inch square pieces of different colored construction paper.
Scatter the paper over an area on the grass. Be sure there is an equal amount of paper used for each color and they include both natural and bright colors. Give the students 30 seconds to collect and then have them count and graph the colors found. The bright colors are almost always n high number and the greens and browns are low. It is more difficult to see them. Point out animal coloration and the need for protection.
Pencils Through the Water Bag
Equipment: Plastic quart bags with twist ties, water, several round pencils
Fill the bags with water (about ¾ full) Gather the top of the bag and seal with twist ties or rubber bands. (Bags that are over-filed stretch and may leak when punctured. You may want to have many bags filed ahead of time and lots of sharpened pencils read to go)
Hold the bag by the top and push a sharpened pencil completely through both sides of the bag. Young children may need help holding the bag and pushing the pencils through.
Discuss air pressure and water pressure and a demonstration of gravity when a pencil is removed.
Magnification
Equipment: variety of objects, magnifying glass
Collect a variety of objects that children can look at through a magnifying glass. Move the glass different lengths away from the object so that the children have the opportunity to see different magnifications.
Conduction
Equipment: bowl, water, pencil, wooden spoon, metal spoon.
Fill a bowl with hot water. Dip a pencil or wooden spoon into the water and hold it there a few seconds. Does it feel warm? (it won’t; wood is not a good conductor of heat). Hold a metal spoon in the water. Test to make sure the spoon is touchable: not too hot. Does it feel warm/ Why? Try some other objects. Heat travels through metal but not through wood.
Chemical Reaction
Equipment: chicken bone, vinegar, jar
Place a chicken bone in a jar of vinegar. Wait five days. The bone will be soft.
Osmosis
Equipment: Water, glasses, food coloring, celery, knife
Color water in two glasses different colors. Place the glasses next to each other. Split a large stalk of celery about halfway up. Put one side of the celery in one glass and one in the other. Note how the water colors the celery (takes about 2 hours) Remove the celery from the water and cut across the stalk. Explain how the water goes up in the stalk. (note; a white carnation works, also).
Air Pressure
Equipment: paper cup, sheet of paper, pin or needle to punch hole
Make a small hole in the bottom of a paper cup. Put a sheet of paper on the table and et the cup on it, bottom up. Suck through the hole and lift the cup; the paper will lift also.
Magnetic Force
Equipment: variety of metal and nonmetal objects, magnets
Place a variety of metal and nonmetal objects on the table. Students will experiment with a magnet to determine which items the magnet will pick up. Have students experiment with the force of the magnet by picking up items through paper, wood, glass, etc.
What Will Float?
Equipment: tub of water, wooden stick, paper clip, cotton ball, rubber band, crayon, marble, pencil
Have students guess which items will float. Students insert each item, one by one, into the water to check their forecast. Make a table on paper for students to record their observations.
Paper Hop
Equipment: piece of notebook paper, paper hole punch, table, balloon (use a size easily held in ones’ hand)
Use the hole punch to cut 15-20 small circles from the piece of paper. Separate the circle and spread them on a table Inflate the balloon and tie it. The student will rub the balloon against his/her hair, about five strokes It is important that the hair be clean, dry and free from oil. The student will hold the balloon close to, but not touching, the paper circles.
The paper circles will hop up and stick to the balloon.
This works because paper is an example of matter and all matter is made up of atoms. Each atom has a positive center with negatively charged electrons spinning around the outside. The balloon rubs the electrons off the hair, giving the balloon an excess of negative charges. The positive part of the paper circles is attracted to the excessive negative charge on the balloon. This attraction between the positive and negative charge is great enough to overcome the force of gravity, and the circles will hop upward toward the balloon.
Water Pressure and Depth
Equipment: tin can about 18 inches tall with three holes near the bottom, the center and the top, water
Put one finger over each hole in the can. Ask someone to fill the can with water. Take all three fingers off the three holes at the same time.
The water squirts out of the lowest hole with the most force and out of the top hole with the least force. Water pressure becomes greater as the water becomes deeper.
Magic Drawing
Equipment: baking soda, water, white paper, paintbrush, grape juice
Mix a solution of ¼ cup baking soda to 1 cup water. Draw a picture or design with the baking soda solution on the white paper using the paintbrush. Let paper dry completely. It will appear blank. Pour the grape juice into a small bowl. Use a new paintbrush to paint over the paper with the grape juice. The baking soda picture will magically appear in green.
The acid of the grape juice causes a chemical reaction with the alkali of the soda to form the green color.
What Is Going On?
Equipment: two glasses, salt, water, two eggs
Fill two glasses with water. Add 12-15 teaspoons of salt to one glass. Mix thoroughly. Add an egg to each glass. Observe what happens.
The salt made the water heavier. The salt water now supports the egg. This is true for other items. Ships and everything else that floats will float easier in salt water.