This lesson uses station activities to spark inquiry about air having mass. My goal is to give students the background knowledge and experiences to explain that air has mass and exerts pressure.
Students will then model their understanding by creating a short video, presentation, poster, etc.
I ask students if air is matter as a do now question. I want to activate students' prior knowledge that matter is anything that takes up space and has mass. This will be revisited when we reflect on what we learned from each station activity. I want students to think about a very broad idea and then build understanding as they collect, analyze data and develop models.
In terms of responses, there are two common answers: 1) Students think that if it cannot be seen then it can't be matter or 2) Students understand that air is matter and justify their ideas based on the fact that they breathe air. If they breathe something then it must exist (be matter).
Students will later use Claims-Evidence-Reasoning (CER) to support their arguments that air has mass tomorrow in class after we review their HW assignment, which is to model their understanding of one of the demonstrations.
This link to Science Matters gives an overview of the balloon in a bottle activity.
Students perform the experiment and record their findings in their science notebooks.
Students follow the directions for Station 1 in Air Station Procedures. Everything should be recorded in their notebooks.
This video highlights how students should transition to the next station:
Students should perform both can activities and record their findings in their science notebooks.
Students should follow the procedure 1 on this sheet that is left in the middle of the desks for each group to read prior to beginning the activity.
Students should be given materials to perform this activity.
Demo explanation for teachers:
Prior to students blowing between them, the cans don't move. They are stationary because the air pressure surrounding them is equal, therefore, movement doesn't occur. When students blow between the cans, they roll towards each other because the pressure between them is now lower. This results in the higher pressure surrounding the cans to push them together. Our goals as teacher who are implementing the NGSS is to get them to eventually model this phenomenon at the molecular level.
Students should follow the procedure 2 on this sheet that is left in the middle of the desks for each group to read prior to beginning the activity.
Students should make predictions and record what happened in the demonstrations.
Explanation for teachers:
Similar to the can demonstration, the card falls when students blow under it through the creation of lower pressure. The higher pressure above the card then pushes the card down. The same is true when a student blows on the top of the card, because the higher pressure created by the force of their breath causes the molecules under the card to disperse outward, making the card lay flat.
Depending on time, you may have to assign toward the end of this class or for homework. Now that groups have experienced all 3 demonstrations it is time for them to make sense of what they have experienced.
Groups should pick one of the demonstrations and then create a model that explains what is causing the phenomenon to occur.
Each model should include:
1) A detailed picture that depicts the demonstration and results
2) An explanation of what was observed
3) A detailed explanation of what the group thinks is happening that causes phenomenon to occur