Elementary school is the perfect opportunity to foster a love for science through hands-on activities. If you ask any child what their favorite school activity is, they will almost always name a project that let them get their senses involved. Children learn by play and science experiments open their eyes to a whole new way of learning.
When the study of astronomy begins in the classroom, children will be fascinated with stories of stars, planets, and spaceships. It seems a little far fetched to think they can get any hands on experience on this subject, but there are two experiments that are perfect for young children to study space.
First, children can work together to make a homemade sundial. Sundials are the oldest way to tell time, and they use the sun’s position to gage the time of day. As the earth rotates around the sun, it gives us the illusion that the sun is moving, rising in the east and setting in the west. As the sun travels across the sky, the post in the center of a sundial will cast shadows on different marks which indicate the time. It’s just like reading a clock and even kids will enjoy this primitive method of telling time!
To create your sundial, you will need:
1. A large styrofoam cup with a plastic lid and straw
2. A wristwatch
3. A permanent marker
4. A pencil
5. Tape
6. Some small pebbles (enough to fill the cup halfway)
7. A compass
To create your sundial, complete the following easy steps.
1. Use the pencil to poke a hole in the side of the cup, about two inches below the top.
2. Fill the cup halfway full with pebbles so it doesn’t tip over.
3. Put the lid on the cup.
4. Put the straw through the hole in the lid and the hole in the side of the cup. Let it stick out about half an inch from the side.
5. Tape the straw to the cup.
Now that you’re finished building your sundial, you are ready to give it a try. Let students watch the shifting shadows as the sun moves through the sky. Help them keep a scientific log of where the shadows are each hour of the day. Track the changes for three days and they will learn the pattern of telling time with their homemade sundial.
A second great experiment for elementary students is making a comet. This experiment will take about two days to complete and the NASA website has complete instructions. Begin your experiment by reading “Maria’s Comet” by Deborah Hopkinson. Then you are ready to demonstrate how an actual comet might look.
You will need:
1. 2 cups of water
2. 2 cups of dry ice (make students wear heavy rubber gloves for safety!)
3. 2 tablespoons of sand or dirt
4. ammonia
5. dark corn syrup
6. ice chest
7. newspapers
8. four medium sized trash bags
9. heavy duty rubber gloves
10. hammer
11. large mixing bowl
12. large wooden spoon
13. paper towels
14. hair dryer (optional)
Now you are ready to make your comet. Follow these instructions:
1. Cut open a trash bag and use it line the mixing bowl.
2. Have all ingredients and utensils arranged in front of you.
3. Pour water into the bowl.
4. Add sand or dirt, stirring well.
5. Add a dash of ammonia.
6. Add a dash of corn syrup, stirring well.
7. Place the dry ice into 3 trash bags that have been layered together. Be sure to wear heavy rubber gloves while handling the dry ice so you don’t get burned.
8. Crush the dry ice by pounding it with the hammer.
9. Add the dry ice to the rest of the ingredients in the bowl, while stirring vigorously.
10. Continue stirring until the mixture is almost frozen.
11. Lift the comet out of the bowl using the plastic liner and shape it like a snow ball.
12. Unwrap the comet as soon as it is frozen enough to hold its shape. Now you can place the comet on display for the rest of the day as it begins to melt and sublimate (turn from a solid to a gas).
Explanation:
As the comet begins to melt, the class will notice little jets of gas coming from it. This is where carbon dioxide is escaping through small holes in the frozen surface. This happens with real comets, and the jets can dispel enough gas to change the orbits of the comet. After several hours, the comet will look like a crater-filled ball of ice. Real comets are depleted by sublimation in this same way each time they come near the sun. They might break up or completely disintegrate while they travel through space. Sometimes comets have a solid rock core that is left behind to travel in orbit as a dark asteroid.
