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Teacher Education through School-based Support in India www.TESS-India.edu.in Using questions to extend students’ understanding of forces Unit 5: Elementary Science http://creativecommons.org/licenses/

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Teacher Education through School-based Support in Indiawww.TESS-India.edu.in

Using questions to extend students’ understanding of forces

Unit 5:

Elementary Science

http://creativecommons.org/licenses/

The TESS-India project (Teacher Education through School-based Support) aims to improve the classroom practices of elementary and secondary teachers in India through student-centred and activity-based approaches. This has been realised through 105 teacher development units (TDUs) available online and downloaded in printed form. Teachers are encouraged to read the whole TDU and try out the activities in their classroom in order to maximise their learning and enhance their practice. The TDUs are written in a supportive manner, with a narrative that helps to establish the context and principles that underpin the activities. The activities are written for the teacher rather than the student, acting as a companion to textbooks. TESS-India TDUs were co-written by Indian authors and UK subject leads to address Indian curriculum and pedagogic targets and contexts. Originally written in English, the TDUs have then been localised to ensure that they have relevance and resonance in each participating Indian state’s context. TESS-India is led by The Open University and funded by UKAID from the Department for International Development. Version 1.0 Except for third party materials and otherwise stated, this content is made available under a Creative Commons Attribution-ShareAlike licence: http://creativecommons.org/licenses/by-sa/3.0/

ContentsIntroduction 1

Learning outcomes 2

1 Exploring questioning 3

2 Bloom’s Taxonomy 4

3 Using Bloom’s Taxonomy 7

4 Questioning in everyday teaching 10

5 Using questions for assessment 16

6 Encouraging students to ask questions 17

7 Summary 18

8 Resources 19

Resource 1: Rolls-Royce activity sheet on ‘Forces and airresistance’ 19Resource 2: Rolls-Royce teachers' notes on ‘Forces and airresistance’ 24

9 Related units 28

References 29

Acknowledgements 30

Transcript 31

IntroductionGood questioning skills are an essential part of teaching in the elementaryscience classroom. A teacher should use a range of questions throughouttheir lessons to check their students’ understanding, structure their learning,prompt their thinking and maintain their involvement. Through skilfulquestioning, a teacher can modify their students’ knowledge andunderstanding of scientific concepts.

Carefully structured questioning can promote higher-order thinking duringinvestigative work and can support the development of essential skills ofenquiry such as prediction and evaluation.

In addition to using questions themselves, teachers should also encouragestudents to formulate and ask their own questions, as a means of mediatingtheir own learning.

This unit will explore how careful questioning can be used to support andencourage learning in the elementary science classroom.

1

Introduction

Learning outcomesAfter studying this unit, you should be able to:

. use a variety of different question types in your elementary scienceteaching

. encourage your students to ask questions about the science topics theyare learning.

TDU 5 Using questions to extend students’ understanding of forces

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1 Exploring questioning

Pause for thought

. Why is questioning important in the elementary science classroom?

. In what ways can it help your students? Make a note of any ideas

that come to mind.

Here are some possible ideas you may have noted down. Questioning helpsto:

. establish students’ prior knowledge and understanding

. focus students’ thinking in relation to a specific scientific concept orprocess

. engage and motivate students

. highlight any scientific misconceptions that students might have

. challenge and extend their scientific knowledge

. support the students in applying their knowledge and understanding

. support students in scientific enquiry (observing, hypothesising,predicting, evaluating and concluding)

. give students a sense of ownership of what is being learnt

. maintain the pace and flow of the lesson.

Types of questioning

Good questioning can have a direct impact on student progression. However,not all types of questions are effective in facilitating learning.

You may be familiar with the distinction between ‘closed’ and ‘open’questions. If so, can you give an example of each type?

A closed question is one that is limited to a single ‘correct’ answer,including ‘yes’ or ‘no’. Examples of closed questions are:

. If I push the ball, will it move?

. Is ‘pushing’ a force?

Closed questions like this are useful to check your students’ recall ofinformation or to guide their understanding of a process. Open questions, incontrast, invite a range of responses and encourage students to think.

Examples of open questions include:

. What would happen if there was no friction on our planet?

. Can you describe all the possible ways you could move this ball?

These questions will require students to apply their knowledge andunderstanding in order to answer the question.

3

1 Exploring questioning

2 Bloom’s TaxonomyIn 1956, Benjamin Bloom classified the different intellectual behaviours thatwere important to learning. He identified behaviours that required lesscomplex thinking, such as information recall or recognition of facts, andthose that placed higher cognitive demands on students such as evaluating.He devised a hierarchy of intellectual behaviours, ordering them from lower-to higher-order thinking.

As part of his research, Bloom studied thousands of questions asked byteachers and categorised them according to the hierarchy he had devised. Hediscovered that over 90% of teacher questioning required students to thinkonly at the lowest possible level, and that this thinking was mainly related toinformation recall.

Table 1 shows the six categories of questions that Bloom defined, commonlyreferred to as Bloom’s Taxonomy.

Table 1 A summary of Bloom’s Taxonomy.

Thinkinglevel

Categories Thinking behaviours Example types ofquestions

High Synthesis Inventing, imagining,hypothesising, creating,devising

What would happen if…?

How many ways canyou …?

How might you solvethis problem?

Can you design a … to…?

Can you of anotherway to …?

Evaluation Debating, justifying,assessing, prioritising

Why do you think …?

Can you think ofanother solution to thisproblem …?

How effective is …?

Analysis Criticising, comparing,investigating,categorising

How does this comparewith …?

What was the problemwith …?

What are the reasonsfor …?

Why do you think thishappened?

TDU 5 Using questions to extend students’ understanding of forces

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Middle Application Applying, transferring,showing

Can you give meanother example of …?

Can you writeinstructions for …?

What factors could youchange?

What else has thesame characteristics as…?

Low Comprehension Restating, discussing,summarising

Can you write … inyour own words?

Can you tell me whathappened when …?

What does … mean?

Knowledge Locating, recalling,listing, describing

Can you list …?

Describe whathappened.

What is …?

Can you find theanswer to …?

This first activity will encourage you to reflect on your own classroomquestioning skills.

Activity 1: What questions do you ask yourstudents?

Choose a 5–10 minute section of an elementary science lesson that you

are due to teach.

If you have access to an audio recording device, place it on the desk

and record yourself. After the lesson, replay the recording, writing out all

the questions that you asked your students. Alternatively, you could ask

a colleague to observe part of your lesson and note all the questions

that you ask during that time. Perhaps you could offer to do the same

so you can focus on improving your questioning skills together?

The grid in Table 2 is copied from Table 1. Use it to categorise the

questions that you have used in your teaching. Refer back to the

examples in Table 1 if you find them helpful.

5

2 Bloom’s Taxonomy

Table 2 Grid for categorising your questions.

High Synthesis

Evaluation

Analysis

Middle Application

Low Comprehension

Knowledge

Pause for thought

. What type of questions did you use the most? Did this surprise you?

. How could you change some of your lower-level questions into

higher-level questions?

TDU 5 Using questions to extend students’ understanding of forces

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3 Using Bloom’s TaxonomyIn the next activity, you will reflect on another teacher’s use of questioningand consider what impact this had on her students’ learning.

Activity 2: Observing a teacher using questioning

Now watch the video below about of a teacher developing her students’

understanding of a ‘fair test’ (see TDU 13, Practical investigations:

exploring seed germination for more on using fair tests in the

elementary science classroom). If you are unable to watch the video, it

shows the teacher using questioning to ensure that her students are

conducting a fair test by changing one factor (or variable) at a time, and

drawing attention to the use of equal force when pushing objects. You

may also find it useful to read the video’s transcript.

Now watch the video clip. If it is unavailable or has not been

provided separately, you can find it at the TESS-India YouTube

channel. You will find the transcript at the end of this unit.

After watching the video, read the list of questions used by the teacher

and classify them according to Bloom’s Taxonomy, using the grid below.

You may wish to watch the video again before completing this activity.

1 ‘T’ stands for …?

2 What did you do with the tennis ball?

3 What did you do with the paper ball?

4 You pushed the paper ball. Why?

5 But do you think it was right?

6 Did you treat both balls in the same way?

7 What should you do?

8 Was that a fair test?

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3 Using Bloom’s Taxonomy

9 What were the results?

10 What did you see?

11 Which ball moves faster?

12 Why do you think the tennis ball was going further?

13 What about the paper ball?

14 How was the surface of the slope? [pointing to the slope used]

15 What if we tried rolling balls on a different surface?

16 What kind of surface could we use for our next experiment?

17 So if I spread a cloth on this [points to slope], will that make it

rough and uneven?

Table 2 Grid for categorising your questions.

High Synthesis

Evaluation

Analysis

Middle Application

Low Comprehension

Knowledge

TDU 5 Using questions to extend students’ understanding of forces

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Answer

High Synthesis 15. What if we tried rolling balls on adifferent surface?

16. What kind of surface could we usefor our next experiment?

Evaluation 12. Why do you think the tennis ball wasgoing further?

13. What about the paper ball?

Analysis 4. You pushed the paper ball. Why?

Middle Application

Low Comprehension 2. What did you do with the tennis ball?

3. What did you do with the paper ball?

7. What should you do?

9. What were the results?

10. What did you see?

Knowledge 1. ‘T’ stands for …?

5. But do you think it was right?

6. Did you treat both balls in the sameway?

8. Was that a fair test?

11. Which ball moves faster?

14. How was the surface of the slope?[pointing to the slope used]

17. So if I spread a cloth on this [pointsto slope], will that make it rough anduneven?

At the beginning of the experiment, the teacher checked her students’

understanding by using factual questions that had a limited number of

answers. As the investigation progressed, she used problem-solving

questions that required her students to think more abstractly. The

students responded to these questions in a variety of ways,

demonstrating their understanding of forces in action.

Look back at the list of questions asked by the teacher. Which were the

most effective in changing and developing her students’ ideas about

forces? What impact did these have on her students’ learning?

9

3 Using Bloom’s Taxonomy

4 Questioning in everyday teaching

Pause for thought

. How have you supported your students in answering your questions

in class?

. Can you identify the students in your class that are particularly good

at answering questions? What skills do they have that help them do

this?

Supporting your students to move from giving simple responses to engagingin complex, potentially conflicting sets of answers can be challenging,especially if they are not used to having interactive discussions. A series ofwell-structured, challenging questions will have limited impact on learning ifyour students are unused to responding to them.

The following suggestions may help you to develop answering skills amongyour students:

. Be sure to allow your students sufficient thinking time to respondthoughtfully to your questions.

. Vary your approach from lesson to lesson, by asking students to think ofthe answers to your questions individually on some occasions and toshare their ideas in pairs or small groups on others.

. Manage your students’ answers so that each response contributes to thelearning process. Sometimes a single answer will be sufficient. This ismost likely with closed questions. With open questions, a full range ofanswers will be more valuable. In this case, you should encourageseveral different students to respond.

. Vary the way you select students to respond, by choosing from amongthose who have volunteered to answer (by putting their hand up) onsome occasions and selecting from those who have not volunteered onothers. Alternatively, agree a ‘no hands up’ question-and-answer session,with you differentiating the nature of the questions and selectingappropriate respondents according to their ability. This inclusive approachcan build all the students' confidence.

. Introduce an ‘ask a friend’ option to answering questions. If a student isstruggling to answer a question, they have the right to ask a friend tohelp them with their response. This form of public peer collaboration canbe both useful and fun, while removing some of the stress associatedwith answering questions on one’s own.

TDU 5 Using questions to extend students’ understanding of forces

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Case Study 1: Mrs Das tries higher-levelquestioning while teaching forces

Mrs Das, a Class II teacher, was beginning an elementary science topic

on forces. She wanted her students to have direct experience of forces

and their effects. She therefore decided to take her class to an outdoor

area of the school grounds to explore forces in action. She set up three

activities, each with a different set of equipment, next to which she

placed some instructions, followed by two questions. She then

organised the class into three groups, each of which spent ten minutes

at each activity before moving on to the next one. Read how she went

about incorporating questioning into the activity.

I had recently learned about higher-level questioning and the impact it

could have on students’ learning. I wanted to use this kind of

questioning to encourage my students to observe and analyse forces

while they were playing with the different equipment I had arranged on

each table.

These are the three activities that I set up, together with the

accompanying questions and some of the answers my students gave.

Rope Pull

I placed some ropes on the ground and asked three students to stand at

each end of each of a rope. I asked the students at one end of the rope

to pull, while the other students held the other end. They then swapped

roles and did the same. Due to the risk of injury, I supervised this

activity to ensure that the students did not pull the rope too hard.

These are the two questions that I asked my students, followed by a

selection of their responses.

Q. What would happen if everyone stopped pulling the rope?

A. No one would move because no one would be pulling.

A. Ropes don’t move by themselves. They need a force to make this

happen.

Q. Why should you not pull the rope too hard?

A. If we pulled hard, it could make the other students fall over.

A. If we pulled gently, the other students would only move a little bit.

11

4 Questioning in everyday teaching

Balls and Bean Bags

On this table I placed a selection of large and small balls, together with

some bean bags.

These are the two questions that I asked my students, followed by a

selection of their responses.

Q. How can you control the speed of a ball?

A. If you kick the ball hard, it moves a long way away, but when you tap

it gently, it only moves a little bit.

A. When you use a little bit of force, it moves softly. When you use all

your strength, it goes really fast.

Q. How does rolling a bean bag compare with rolling a ball?

A. The ball rolls easily but the bean bag does not really roll. You have to

keep pushing it. The bean bag can’t roll because it isn’t the right shape.

Flour Dough

The previous night I made a simple flour dough with water and

vegetable oil. I placed small balls of dough onto a plastic sheet.

These are the two questions that I asked my students, followed by a

selection of their responses.

Q. What types of shapes can you make with the dough?

A. I made lots of shapes. I made a ball, a snake and flat bread.

A. I made a face by poking my fingers into the dough.

Q. What did you do to change shape of the dough?

A. I rolled, pulled and squashed the dough.

A. I used the force of my hand to make it flat and pushed my fingers

into it to make holes.

Mrs Das reflects on the activity

I could tell that my students really enjoyed this outdoor activity. I felt that

by the end of the lesson they had a good practical understanding of

forces. On our return to the classroom, I gave them ten minutes to

prepare a short report of their findings. They established that pushing

and pulling made objects change their shape, speed and direction. They

recognised that a force was required for an object to move.

By allowing my students time to explore and reflect before responding to

the questions I had prepared, I helped them achieve a better

understanding of forces. I intend to prepare key questions as part of my

TDU 5 Using questions to extend students’ understanding of forces

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lesson planning in future as I find them useful in structuring my

teaching.

In the next activity you will prepare a sequence of questions that willencourage your students to use higher-order thinking.

Activity 3: Preparing a lesson plan to teach gravityand air resistance

The lesson plan below aims to help students to investigate gravity and

air resistance. It is based on the lesson plan template in TDU 1,

Resource 3.

The lesson plan does not yet contain questions. Using Bloom’s

Taxonomy (Table 1) for support, write down the questions that you will

ask your students at each stage of the lesson. Think of the questions

that you will ask at the beginning of the lesson, during the main activity

and during the discussion at the end.

You can adapt the plan according to the needs of your class. You may

also wish to consider questions that could challenge your more able

students and questions that could support those who need more

guidance.

Resource 1 and Resource 2 near the end of this unit provide some

activity materials related to air resistance.

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4 Questioning in everyday teaching

Objectives (withdates)

Main teaching Independent/groupactivity

Elementary sciencetopic focus: Physicalprocesses/forces

Lesson introduction:How will you engageyour students duringyour lessonintroduction? Forexample, will you usemini tasks, paireddiscussion, hands-ontasks, games, etc.?

Pick up threeclassroom objects anddrop them. Askstudents in pairs todiscuss why theobjects fell to theground and note theirideas. Draw an objectwith an arrowindicating the force ofgravity. Write ‘gravity’on the board andagree a brief definition.

Explain that in thefollowing activitystudents willinvestigate the forcesthat will slow downobjects as they movethrough the air towardsthe ground.

Students’ activity:What will the studentsdo? How will this helpthem meet theobjectives?

Organise students intogroups and providethem with a piece ofpaper, a stopwatch anda cotton wool ball.

Ask the students todrop the paper andtime how long it takesto reach the ground(repeat several timesto get an accuratereading). Ask thestudents to change theshape of the paper andrecord how long ittakes for the paper toreach the ground.Repeat the activity withthe cotton wool ball.Encourage the childrento make a ‘fair test’.

After the investigation,ask each group toprepare a short reportof their findings to theclass, including thedata collected anddiagrams which help toexplain the forcesacting on the objects.

Objectives: What arestudents going tolearn?

Gravity is a force thatpulls objects to theground.

Friction, including airresistance, is a forcethat slows a movingobject.

Outcomes: Whatshould the students beable to do at the endof the lesson?

Say what forces act onan object as it falls tothe ground.

Describe what airresistance is and howit can slow down amoving object.

Support: How willlower-achievingstudents besupported?

Remind the studentsabout any previouswork relating to forces.Draw a set of diagramsusing arrows toindicate the forcesworking on the paperin various shapes.Once these have beendiscussed with thestudents ask them todrop the paper and tellyou what is happening.

TDU 5 Using questions to extend students’ understanding of forces

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Scientific vocabularyand definitions:

friction

air resistance

gravity

force

streamlined

Questions: What willyou ask your studentsduring your teaching?

Extension/challenge:How will higher-achieving students bechallenged?

Give students a pictureof two different sizedparachutes and askthem to explain whichparachute would fallthe fastest and why.This could be tested inanother lesson.

Plenary: How will youconclude your lesson?

Allow each group toreport their findings.Brainstorm everydayobjects that have beendesigned to increaseor decrease airresistance. Encouragestudents to askquestions about airresistance which couldform the basis offurther classinvestigation.

Assessment: How willyou know the studentshave met theobjectives? What arethe opportunities forCCE during thislesson?

Were the students ableto explain why anobject falls to theground? Could theydescribe, verbally orthrough the use of adiagram, how airresistance works toslow an object down?

Did they know that bychanging the design ofan object they canincrease/decrease airresistance?

Pause for thought

. Did you use questions that encouraged a variety of ideas and

responses from your students? How did your questions support or

challenge your students' thinking?

. Do you think the use of questions in your lesson encouraged your

students to explore the concept of air resistance? Will you prepare

questions in advance for future lesson plans?

15

4 Questioning in everyday teaching

5 Using questions for assessment

Continuous and comprehensive evaluation (CCE)

Questions are a common way of checking your students’ understanding

of concepts and processes so that you can modify your lesson plans

according to your students' needs. Using open-ended questions can

help you assess your students’ attainment at the end of a lesson or

study topic, by providing opportunities for them to demonstrate their

increased understanding over time.

Here are some sample questions that could be used with students after

completing investigative work on gravity, friction and air resistance.

. What are the forces that act on an object as it falls to the ground?

. What is the effect of friction on an object in motion?

. Why do some objects have more than one force acting on them at

once?

. How would you change an object to decrease its air resistance?

. Why would you want to increase frictional forces on a moving

object?

. What would happen if the Earth’s gravitational pull was decreased to

half?

Students may answer questions verbally or record their responses on

paper, accompanied by pictures or diagrams where appropriate.

TDU 5 Using questions to extend students’ understanding of forces

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6 Encouraging students to askquestionsQuestioning is not something only teachers should do. Rather, studentsshould be encouraged to do so as well. Skilful teacher questioning,especially of the higher-order open type, should prompt students to formulatetheir own questions about the topic as they consider possible answers.Students’ questions can be very revealing – in demonstrating theirimagination and curiosity, in providing a different perspective on a particularissue and in displaying misunderstandings or gaps in their knowledge.

It is important to ensure that students feel comfortable about askingquestions in the classroom especially if they are not used to doing this. Besure to value all their contributions. If a student’s question displays someform of misunderstanding, it is very likely that some of their peers will havesimilar misconceptions. You can therefore use the opportunity to clarifyissues with the whole class. Inviting other students to provide possibleanswers is often much more rewarding than responding yourself.

The following activity is designed to develop students’ questioning andanswering skills.

Hot Seating

Hot seating can be done as a whole-class activity or in several groups

of six to eight. It is best done as a short introductory or review activity in

relation to a current topic.

A volunteer students takes a seat in front of the class or their group and

answers questions about the topic from their peers.

Using prompt cards with the questions ‘Who?’, ‘What?’, ‘Why?’,

‘Where?’, ‘When?’ and ‘How?’ will encourage students to formulate

questions that require more complex answers. Questions that include

these words cannot be answered with a simple ‘Yes’ or ‘No’.

Question stems can be displayed in class, and modelled by the teacher,

to encourage students to formulate higher-level questions. Examples

might include:

. What other way could you …?

. Is there a better solution to …?

. Why did … happen?

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6 Encouraging students to ask questions

7 SummaryThis unit has demonstrated how carefully prepared questions can extendstudents’ knowledge and understanding of concepts in the elementaryscience classroom. By improving your questioning skills, you can have adirect impact on your students’ attainment. Similarly, by using a rich varietyof questions, including those that require students to use higher-orderthinking skills, you will not only motivate and engage your students butprovide them with a foundation to help develop their critical thinking.

The unit has outlined a number of ways of supporting students whenanswering questions, and finished by stressing the importance of encouragingstudents to ask questions themselves, as these can provide valuablecontributions to the learning process.

TDU 5 Using questions to extend students’ understanding of forces

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8 ResourcesResource 1: Rolls-Royce activity sheet on‘Forces and air resistance’

Rolls-Royce PLC, a leading company in aerospace design andmanufacturing, has produced a four-page activity booklet for students aged 7to 11 that invites students to identify the forces that act on an object as itfalls to the ground. The booklet (in English) describes what air resistance is,and encourages students to modify air resistance to produce lift.

19

8 Resources

Forces and Air

Resistance

For pupils aged 7-11

Activity sheet

This Activity Sheet is provided by Rolls-Royce plc as part of our continuing

commitment to education

Forces and Air Resistance

When a football is kicked into the air, as it starts to fall back down two forces are present.

Gravity

Air Resistance

Gravity pulls the ball down towards the ground but as the ball falls the air pushes back against the

ball. This force is called Air Resistance.

These forces are shown on the picture above by arrows.

The arrows show the direction of the forces. A longer arrow means a larger force.

Air resistance always pushes in the opposite direction to the way the object is moving.

The air resistance pushing back on an object can be changed by changing the shape of the object.

For example the shape of a parachute traps the air which pushes back to give a high air resistance.

Forces and Air Resistance

For each pair of the following pictures use arrows to show the direction and size of the air

resistance. Under each pair write a sentence to say what the air resistance does. Say whether you

think the air resistance is useful or is a problem.

Bike with high handle bars Parachutist. Chute is NOT open

Parachutist. Chute IS open

Bike with low handle bars

Lorry with shaped cab Lorry with square cab

Forces and Air Resistance

As an aeroplane takes off the force pushing it forward comes from the powerful gas turbine

engines. This force is called thrust.

The picture below shows an aeroplane flying

level. The force acting upwards is called lift.

This force happens because of the special

shape of the aeroplane wings.

Lift

On the picture use arrows to show the direction of three other forces:

The thrust from the engines

The air resistance

The force of gravity.

Resource 2: Rolls-Royce teachers' noteson ‘Forces and air resistance’

There is also an accompanying four-page booklet of ‘teachers' notes’.

TDU 5 Using questions to extend students’ understanding of forces

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Force and Air

Resistance

For pupils aged 7-11

Teachers’ notes

This Activity Sheet is provided by Rolls-Royce plc as part of our continuing

commitment to education

Forces and Air Resistance

Forces and Air Resistance

For each pair of the following pictures use arrows to show the direction and size of the air

resistance. Under each pair write a sentence to say what the air resistance does. Say whether you

think the air resistance is useful or is a problem.

Bike with high handle bars Parachutist. Chute is NOT open

Parachutist after chute opens

Bike with low handle bars

On the bicycle with the high handlebars the

person will have more air resistance. This will

slow them down and make it more difficult for

them to pedal.

When the parachutist opens their parachute

the air resistance increases. This slows the

parachutist down and lets them land safely.

Lorry with shaped cab Lorry with square cab

The Lorry with the shaped cab will have less

air resistance. This lorry will use less fuel. It will

cause less pollution and be cheaper to run.

Forces and Air Resistance

Forces and Air Resistance

The picture below shows an aeroplane flying level. The force acting upwards is called lift. This force

happens because of the special shape of the aeroplane wings.

On the picture below use arrows to show the direction of three other forces:

The thrust from the engines

The air resistance

The force of gravity.

Lift

Gravity

Forces and Air Resistance

Practical tips

On these activity sheets arrows are used to show both the direction and size of forces. The longer

the arrow the bigger the force.

The first sheet illustrates how gravity acts to pull an object, in this case a football, towards the Earth.

As the ball accelerates downwards it has to move through the air which resists it with an upward

force, air resistance. This is a difficult concept for children to understand, but it is really just a

particular example of friction. The ball rubs against the air particles which have to be pushed aside

to let the ball pass as it falls.

The next section gives examples of how the shape of an object affects air resistance, the more

streamlined the object is the less air resistance it has, the air pushed to one side can flow smoothly

over the surface causing less air resistance.

The pupils are then asked, mark in the direction of three other forces acting on an aeroplane.

Balanced forces are not a specific teaching point at KS2 but for an aeroplane in level flight the forces

of lift and gravity will be balanced and thrust and air resistance will be balanced.

National Curriculum Links

This investigation links to attainment target Sc 4, Physical processes. At KS2:

Pupils should be taught:

Sc4 2b Pupils should be taught that objects are pulled downwards because of the gravitational

attraction between them and the Earth.

Sc4 2c Pupils should be taught about friction including air resistance, as a force that slows

moving objects and may prevent objects from starting to move.

9 Related unitsQuestioning is a classroom technique that runs through all the ElementaryScience units. The following units are particularly closely linked with theuse of structured questioning.

. TDU 3, Using explanations as a teaching strategy: life processes: Thisunit explores how teachers can use questions to motivate and activelyengage students during large-group demonstrations.

. TDU 7, Sorting and classifying living and non-living things: This unitexplores the role of questioning in supporting students to sort andclassify living and non-living things.

. TDU 13, Practical investigation: exploring seeds germination: This unitexplores the scientific method and identifies ways in which questioningcan enhance scientific enquiry skills.

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9 Related units

ReferencesAdams, R. (1994) Blueprints: Science Assessment Key Stage 1, Surrey, StanleyThornes.

Lancashire Grid for Learning, UK (undated) ‘Science National Curriculum: KeyStage 1’ (online). Available from: http://www.lancsngfl.ac.uk/curriculum/science/download/file/Microsoft%20Word%20-%20Natioanl%20Curriculum%20for%20Key%20Stage%201.pdf (accessed 10January 2014).

Rolls-Royce PLC (undated) Activity sheet on forces and air resistance for pupilsaged 7–11.

Rolls-Royce PLC (undated) Accompanying teachers' notes for activity on forcesand air resistance.

Wikipedia (2014) Bloom's taxonomy [Online], 12 January. Available at http://en.wikipedia.org/wiki/Bloom%27s_taxonomy (Accessed 14 January 2014).

TDU 5 Using questions to extend students’ understanding of forces

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AcknowledgementsThe content of this teacher development unit was developed collaborativelyand incrementally by the following educators and academics from India andThe Open University (UK) who discussed various drafts, including thefeedback from Indian and UK critical readers: Jane Devereux and ChristineJames.

Except for third party materials and otherwise stated, this content is madeavailable under a Creative Commons Attribution-ShareAlike licence:http://creativecommons.org/licenses/by-sa/3.0/

The material acknowledged below is Proprietary and used under licence (notsubject to Creative Commons Licence). Grateful acknowledgement is madeto the following sources for permission to reproduce material in this unit:

Video: appreciation and thanks are extended to the participation of teachersand students at Ramjas School, R.K. Puram and all those involved in themaking of this video.

Resources 1 and 2: activity sheets for teachers and students © Rolls-Royce,http://www.rolls-royce.com.

CCE logo: http://www.cbse.nic.in/.

Every effort has been made to contact copyright owners. If any have beeninadvertently overlooked, the publishers will be pleased to make thenecessary arrangements at the first opportunity.

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Acknowledgements