Communicating matters
View Sequence overviewStudents will:
- identify that air is a gas and that it takes up space.
- change one variable in a fair test investigation about air.
- discuss how the volume of a gas depends on the temperature.
Students will represent their understanding as they:
- discuss, record and compare results of a fair-test investigation.
In this lesson, assessment is formative.
Feedback might focus on:
- students’ fair-testing methods. Are they changing only one variable? Are they measuring and recording data accurately?
Whole class
Class science journal (digital or hard copy)
Demonstration copy of Air temperature investigation planner Resource sheet
Optional: Images and video clips of hot-air balloons being inflated, for example Preparation for a hot air balloon take off (3 minute watch)
Each group
2 x transparent plastic bottles the same size
2 x balloons the same size/thickness, to be fitted over the opening of the bottles
2 x containers deep enough to submerge the bottles
Warm water to fill one of these container*
Ice and tap water to fill the other container*
*Alternatively, you might have communal containers filled with hot and iced water for multiple groups to use.
Note: For this investigation it is ideal for teams to each have two bottles and balloons of the same size, inflated to the same (or as close to) circumference. If enough resources cannot be organised, please allow sufficient time for the bottles/balloons to return to room temperature before submerging in water of a different temperature.
Each student
Individual science journal (digital or hard copy)
Air temperature investigation planner Resource sheet
Safety note
This activity requires the use of hot water and iced water. Consider organising extra adult supervision to support the investigation.
It is recommended that any hot water used in a classroom should be at or below 43°C.
Discuss with students the potential dangers of iced water, and why they should not hold their hands in it.
Lesson
The Inquire phase allows students to cycle progressively and with increasing complexity through the key science ideas related to the core concepts. Each Inquire cycle is divided into three teaching and learning routines that allow students to systematically build their knowledge and skills in science and incorporate this into their current understanding of the world.
When designing a teaching sequence, it is important to consider the knowledge and skills that students will need in the final Act phase. Consider what the students already know and identify the steps that need to be taken to reach the level required. How could you facilitate students’ understanding at each step? What investigations could be designed to build the skills at each step?
Read more about using the LIA FrameworkRe-orient
Review previous learning about the properties of solids, liquids and gases, focusing on gases.
The Inquire phase allows students to cycle progressively and with increasing complexity through the key science ideas related to the core concepts. Each Inquire cycle is divided into three teaching and learning routines that allow students to systematically build their knowledge and skills in science and incorporate this into their current understanding of the world.
When designing a teaching sequence, it is important to consider the knowledge and skills that students will need in the final Act phase. Consider what the students already know and identify the steps that need to be taken to reach the level required. How could you facilitate students’ understanding at each step? What investigations could be designed to build the skills at each step?
Read more about using the LIA FrameworkIdentifying and constructing questions is the creative driver of the inquiry process. It allows students to explore what they know and how they know it. During the Inquire phase of the LIA Framework, the Question routine allows for past activities to be reviewed and to set the scene for the investigation that students will undertake. The use of effective questioning techniques can influence students’ view and interpretation of upcoming content, open them to exploration and link to their current interests and science capital.
When designing a teaching sequence, it is important to spend some time considering the mindset of students at the start of each Inquire phase. What do you want students to be thinking about, what do they already know and what is the best way for them to approach the task? What might tap into their curiosity?
Read more about using the LIA FrameworkChanging properties
Pose the question: Is hot air the same as cold air? Discuss this idea by focusing on how a hot-air balloon works.
- What is a hot-air balloon? What does it look like? What does it do?
- How does a hot-air balloon work?
- What is in a hot-air balloon?
- If air is in a hot-air balloon, why does it go up?
- What might this tell us about what happens when we change the temperature of air?
Optional: View images and video clips of hot-air balloons being inflated.
Heating gases
When heated, the particles in gases gain more energy and try to take up more space (expand).
When heated, the particles in gases gain more energy and try to take up more space (expand). This means that the density (‘mass per unit of volume’ or number of particles in a set volume) of a gas at a certain pressure can vary significantly depending on the temperature.
Hot-air balloons use this principle to rise above the ground. The hot air particles inside the balloon are more ‘spread out’ and less dense than the surrounding air. This causes the balloon to rise above the denser cold air outside the balloon. This is the same principle as when bubbles of air (less dense than water) are pushed to the surface of bodies of water.
When heated, the particles in gases gain more energy and try to take up more space (expand). This means that the density (‘mass per unit of volume’ or number of particles in a set volume) of a gas at a certain pressure can vary significantly depending on the temperature.
Hot-air balloons use this principle to rise above the ground. The hot air particles inside the balloon are more ‘spread out’ and less dense than the surrounding air. This causes the balloon to rise above the denser cold air outside the balloon. This is the same principle as when bubbles of air (less dense than water) are pushed to the surface of bodies of water.
The Inquire phase allows students to cycle progressively and with increasing complexity through the key science ideas related to the core concepts. Each Inquire cycle is divided into three teaching and learning routines that allow students to systematically build their knowledge and skills in science and incorporate this into their current understanding of the world.
When designing a teaching sequence, it is important to consider the knowledge and skills that students will need in the final Act phase. Consider what the students already know and identify the steps that need to be taken to reach the level required. How could you facilitate students’ understanding at each step? What investigations could be designed to build the skills at each step?
Read more about using the LIA FrameworkThe Investigate routine provides students with an opportunity to explore the key ideas of science, to plan and conduct an investigation, and to gather and record data. The investigations are designed to systematically develop content knowledge and skills through increasingly complex processes of structured inquiry, guided inquiry and open inquiry approaches. Students are encouraged to process data to identify trends and patterns and link them to the real-world context of the teaching sequence.
When designing a teaching sequence, consider the diagnostic assessment (Launch phase) that identified the alternative conceptions that students held. Are there activities that challenge these ideas and provide openings for discussion? What content knowledge and skills do students need to be able to complete the final (Act phase) task? How could you systematically build these through the investigation routines? Are there opportunities to build students’ understanding and skills in the science inquiry processes through the successive investigations?
Read more about using the LIA FrameworkDoes air change?
Show students a transparent plastic bottle with a balloon, inflated to have an approximately 15 cm circumference, fitted over the opening.
Through questioning and discussion have students confirm that there is air inside the bottle and balloon.
- What is in the balloon and bottle?
- The balloon and bottle both contain air.
- What are the properties of air(/gas)?
- Can air move in or out of the balloon and bottle?
- The balloon and bottle are a sealed space. Air cannot escape.
- How might we change the temperature of the air inside the bottle?
Pose the question: What things might affect the circumference of the balloon when we submerge this bottle in water?
Using a variables grid, record the variables that could affect the air in the bottle and balloon. Identify that the thing to be measured during the investigation is the circumference of the balloon and place that in the centre of the grid. Brainstorm other variables in the surrounding columns/rows, such as the size of the bottle, the size of the original balloon, how much it is inflated, the temperature of the water. Sections can be added or removed as required.
Note: In some investigations it is appropriate to allow teams to select the variable they wish to change, and teams might select different variables. However, in this case, the goal of the investigation is to make the air inside the bottle expand, thus ‘blowing up’ the balloon. Changing the temperature of the water the bottle is placed into (and thus the temperature of the air inside the bottle) is what will achieve this, so all teams should investigate this same variable.
Use the question stem to write a question for investigation: What happens to (thing to be measured/ dependent variable) when we change (factor that will be changed/ independent variable). What happens to the circumference of the balloon when we change the temperature of the water the bottle is submerged in?
Discuss how the investigation will be conducted and data collected and recorded.
- How could we measure the circumference of the balloon?
- What temperature water might we use?
- How long will the balloon stay submerged?
- How might we record our results?
- labelled diagrams, photos, measurements
In collaborative teams, allow students time to complete their investigation planners, conduct the investigation and discuss and record results.
Writing questions for investigation
A variables grid can be used to turn a broad question into an investigable one.
A variables grid can be used to turn a broad question into an investigable one. Investigable questions are characterised by their clear identification of what is being changed and what is being measured in a fair test, supporting students to investigate a specific physical phenomena.
Investigable questions enable students to plan a fair-test investigation. The question they have devised can be answered empirically, and data can be collected to support and justify claims made.
The Inquire phase allows students to cycle progressively and with increasing complexity through the key science ideas related to the core concepts. Each Inquire cycle is divided into three teaching and learning routines that allow students to systematically build their knowledge and skills in science and incorporate this into their current understanding of the world.
When designing a teaching sequence, it is important to consider the knowledge and skills that students will need in the final Act phase. Consider what the students already know and identify the steps that need to be taken to reach the level required. How could you facilitate students’ understanding at each step? What investigations could be designed to build the skills at each step?
Read more about using the LIA FrameworkFollowing an investigation, the Integrate routine provides time and space for data to be evaluated and insights to be synthesized. It reveals new insights, consolidates and refines representations, generalises context and broadens students’ perspectives. It allows student thinking to become visible and opens formative feedback opportunities. It may also lead to further questions being asked, allowing the Inquire phase to start again.
When designing a teaching sequence, consider the diagnostic assessment that was undertaken during the Launch phase. Consider if alternative conceptions could be used as a jumping off point to discussions. How could students represent their learning in a way that would support formative feedback opportunities? Could small summative assessment occur at different stages in the teaching sequence?
Read more about using the LIA FrameworkDiscussing results
Share and discuss findings as a class.
Encourage students to seek further information and clarification from other teams using the science question starters.
- Did your results match your predictions? Why do you think that happened?
- What happened to the balloon when the bottle was in hot water? Cold water? Why do you think that is?
- What claim could you make about what happens to air when it is heated and cooled based on this investigation?
- If needed, present the claim ‘air takes up more space when it is heated and less space when it is cooled’ and ask students if they would agree and why/why not.
- Could we add another ‘rule’ to the properties we found out about gas? Or more detail to an existing ‘rule’?
- Can you think of any real-life applications of this?
- Hot-air balloons as discussed earlier, soft-drink cans exploding if left in the sun on a hot day, etc.
Reflect on the lesson
You might:
- add to the class word wall of vocabulary related to gases.
- add to the class TWLH chart, completing the H and L sections with what they have learned about gases.
- discuss any challenges students faced during the investigation, and how they might overcome them in the future.
- discuss safety considerations and why they are important.
- discuss how they might use science communication techniques to help other understand what they have learned. Add it to the list created in the Launch phase.
- consider what questions a 'non-expert' might ask them about heating air or other gases.