# This is a lesson about air

Subject:

Science

2

Science Lesson on Air

Sara Broughton

Topic : Air

Concept/Objective : The students will be able to explain how air has weight and occupies space, although we can not see it. Students will also understand that still air has more pushing power than does moving air.

Teaching Materials : a clear plastic bottle, a funnel, modeling clay, two pencils one with flat edges, two identical balloons, string, a long stick, sticky tape, two cans, a bowl of water, a small glass, and a paper tissue

Student Materials : two sheets of paper, a pencil and response pages

Management Strategies : During the first part of the lesson the teacher will be asking questions and performing experiments while the students sit in one big group on the carpet. The students will be encouraged to listen and observe as the experiments are being done. For the second part of the lesson the students will return to their desks to do an experiment on their own and then seat work. Each literature group will called to the rug at different times during the period to read a story about air. The groups not reading will remain in their desks doing seat work until it is their group’s turn.

Procedure : The lesson will begin with a discussion about air. The teacher will ask the class questions to get them thinking about the topic and to see what they know and don’t know about air. Some sample questions are: What can you tell me about air? Does it smell, taste, or weigh anything? How do people use air everyday? How can you tell that there is air around us even though we can’t see it? Next the teacher and students will perform three different experiments to prove to the students that air has weight and occupies space.

Experiment I: Weighing Air

First ask the class some questions and then have them make predictions. Some questions the teacher may want to ask are: Do you think air weighs anything? Why or why not? What do you think will happen when we blow up one of the balloons? Will the stick still balance?

1. Using the long stick, mark the middle of it. 2. Rest the pencil between the two cans and place the middle of the stick across the pencil so the stick is balanced. 3. Use a small piece of sticky tape to fix a balloon onto each end of the stick. Check that the stick remains level-this means that the balloons weigh the same. 4. Unstick one of the balloons and blow as much air into it as you can. 5. Fix it back onto the end of the stick and replace the stick on its center spot. Does the stick still balance? (You could also use a pan balance for this experiment). 6. How could you tell that air weighs? Why did the stick not balance after the balloon was blown up? What would happen if you blew up the other balloon?

Experiment II: Air Needs Space

Ask questions and make predictions: What do you think will happen when we pour water into the funnel? What would happen if I poked a hole in the modeling clay? Will this make a difference? If so, why? What would happen if there was no modeling clay to seal the space between the bottle and the funnel?

1. Put the funnel in the neck of a bottle and seal up the gap using the modeling clay. 2. Pour some water into the funnel. You may be surprised to see that the water does not flow into the bottle. 3. Use one of the pencils to make a small hole in the clay. What happens? 4. Why wouldn’t the water go into the bottle? Why was water able to go into the bottle after we poked a hole in the clay?

Experiment III: Keep the Tissue Dry

Ask questions and make predictions: What do you think is going to happen to the tissue when we put the glass into the water? What would happen if we tilted the glass as we put it in the water? Does it make a difference when you put the glass is straight or tilted? Why?

1. Roll the paper tissue into a small ball and push it into the glass. 2. Turn the glass

upside down and place it under the water in the bowl. You should find that water does not enter the glass and the tissue stays dry. 3. Why did the tissue stay dry? How can you tell there was air in the glass? Why did the napkin get wet when the glass was titled? Why did bubbles come out of the glass when is was tipped? What were in those bubbles?

For the last experiment, Blow the Paper Away, the students will return to their desks and do this on their own. The students will hold two sheets of paper in front of their face and try to blow them apart. The moving air being blown between them should draw the two sheets together instead of separating them. The teacher should have the students first predict what they think will happen and then discuss what actually happened and why. After doing the experiments the students will work on the assignment to assess their knowledge. Literature groups will be called to the carpet to read a story about air. While the groups are reading, the other students should work on the assignment and literature response sheets.

Assessment/Evaluation : To assess the students knowledge give them each a piece of paper with two columns, one labeled “What I Learned About Air” and the second “Questions I Have About Air or What I Would Like to Learn More About Air”. Have the students try to list four things that they learned new about air and then four things they would like to know or questions they might have.

Extension/Integration : This topic will be integrated into reading by having the students break up into their literature groups to read a story about air. Literature response sheets that go along with the story will be given to each student to be done as seat work.