Primary Rocket Car ProjectPrimary Rocket Car Project

Science, ICT, Design and Science, ICT, Design and TechnologyTechnology

The theoryThe theory

This project is designed to bring together children’s skills in science, This project is designed to bring together children’s skills in science, DT and ICT. It is truly cross curricular and was used with classes of DT and ICT. It is truly cross curricular and was used with classes of Year 5 and Year 6 children but could be easily adapted for any Key Year 5 and Year 6 children but could be easily adapted for any Key Stage 2 children. Reception children made an excellent audience Stage 2 children. Reception children made an excellent audience during the test days!during the test days!

The project makes children think about their knowledge of forces and The project makes children think about their knowledge of forces and its application. It is ideal for setting up an exciting fair test with a real its application. It is ideal for setting up an exciting fair test with a real purpose and exploring the variables involved.purpose and exploring the variables involved.

The DT builds on previous skills of making a wheeled chassis and The DT builds on previous skills of making a wheeled chassis and adding the rocket body and there is plenty of scope for thinking about adding the rocket body and there is plenty of scope for thinking about the design in terms of strength and fitness for purpose. Many of our the design in terms of strength and fitness for purpose. Many of our cars were tested to destruction and rebuilt several times!cars were tested to destruction and rebuilt several times!

The ICT spreadsheet skills give purpose to the analysis and the The ICT spreadsheet skills give purpose to the analysis and the presentation of the science results, the graphs illustrate the ease with presentation of the science results, the graphs illustrate the ease with which the technology is used to present easily understandable results.which the technology is used to present easily understandable results.

The other benefitsThe other benefits

The children work in teams to build their ‘team car’. This The children work in teams to build their ‘team car’. This generates a massive amount of discussion, social working, generates a massive amount of discussion, social working, collaboration, division of labour and peer teaching of skills. collaboration, division of labour and peer teaching of skills. The teams can be given real roles such as director, The teams can be given real roles such as director, resource manager, communications officer, mechanic etc. resource manager, communications officer, mechanic etc. The project was run with groups of 4 children and this The project was run with groups of 4 children and this number worked well with all children being involved in number worked well with all children being involved in every stage from design to final presentation. The children every stage from design to final presentation. The children also naturally engaged in self assessment and target also naturally engaged in self assessment and target setting in their enthusiasm to complete the work, often setting in their enthusiasm to complete the work, often coming back at break times to ensure they were on coming back at break times to ensure they were on schedule!schedule!

What resources are neededWhat resources are needed

Time needed is 6, two hour sessions (approx)Time needed is 6, two hour sessions (approx)Session 1 introduction and designSession 1 introduction and designSession 2 build and initial testSession 2 build and initial testSession 3 exploratory testingSession 3 exploratory testingSession 4 accurate fair testingSession 4 accurate fair testingSession 5 spreadsheet construction and data inputSession 5 spreadsheet construction and data inputSession 6 presentation of findings back to the classSession 6 presentation of findings back to the classAlternatively it could feasibly be completed in a themed rocket Alternatively it could feasibly be completed in a themed rocket

or forces project week.or forces project week.

Construction resourcesConstruction resources

I cm squared softwoodI cm squared softwood 4 Wooden pegs for axle holders4 Wooden pegs for axle holders Card trianglesCard triangles 4 Wheels4 Wheels Dowel to fit wheels to form axlesDowel to fit wheels to form axles PVC tubing to slide over dowelPVC tubing to slide over dowel A water proof wood glue (available in DIY stores)A water proof wood glue (available in DIY stores) 2 large cable ties2 large cable ties A 2 litre drinks bottleA 2 litre drinks bottle These are suggested materials, your teams may have These are suggested materials, your teams may have

better ideas for constructing the rolling chassis.better ideas for constructing the rolling chassis.

Chassis dimensionsChassis dimensions

The children will ideally calculate their own frame size for the 2 litre The children will ideally calculate their own frame size for the 2 litre bottle but if you want to pre-build an example or help less able or bottle but if you want to pre-build an example or help less able or younger children these dimensions work well.younger children these dimensions work well.

The frame is held together with card corners and waterproof glue.The frame is held together with card corners and waterproof glue.

Wheels can be of any diameter or material as long as they are glued to Wheels can be of any diameter or material as long as they are glued to the dowel axle. Plastic spacers prevent the wheels fouling the chassis the dowel axle. Plastic spacers prevent the wheels fouling the chassis or bottle and allow the car to run smoothly.or bottle and allow the car to run smoothly.

18cm6cm

13cm axle

1.5 cm plastic tubing spacer

Rocket BodyRocket Body

The body is simply an empty 2 litre drinks The body is simply an empty 2 litre drinks bottle fixed to the chassis. We used large bottle fixed to the chassis. We used large cable ties for ease of fitting and strength.cable ties for ease of fitting and strength.

Completed rolling chassis Chassis with body attached

PropulsionPropulsion

We used the connections from a “ROKIT” We used the connections from a “ROKIT”

kit (£6.89) available from good toy shops kit (£6.89) available from good toy shops

or TTS (www.tts-group.co.uk) -search or TTS (www.tts-group.co.uk) -search

for rokit. The bottle is part filled with for rokit. The bottle is part filled with

water, the bung fitted to the mouth of the water, the bung fitted to the mouth of the

bottle, the tube from the bung attached bottle, the tube from the bung attached

to a bicycle pump (track pumps work to a bicycle pump (track pumps work

best and there is usually one in the PE best and there is usually one in the PE

cupboard that you can borrow!). Pump cupboard that you can borrow!). Pump

air into the bottle until the pressure is too air into the bottle until the pressure is too

great for the bung, the bung is forced out great for the bung, the bung is forced out

and the car will be rapidly propelled and the car will be rapidly propelled

forward leaving a watery trail behind it!forward leaving a watery trail behind it!

Click movie to view it again.Click movie to view it again.

TestingTesting Cars need to be tested outside due to the expulsion of the water. Children have endless Cars need to be tested outside due to the expulsion of the water. Children have endless

enthusiasm for testing but not necessarily scientifically. We had a play session before enthusiasm for testing but not necessarily scientifically. We had a play session before the accurate testing. The only extra equipment needed is a start line and a very long the accurate testing. The only extra equipment needed is a start line and a very long tape measure to record the distances travelled. Containers for water, and a 2 litre tape measure to record the distances travelled. Containers for water, and a 2 litre measuring cylinder for accurate measuring of volumes and a funnel for filling the bottles.measuring cylinder for accurate measuring of volumes and a funnel for filling the bottles.

It is the air/water combination which is being tested everything else MUST be constant:-It is the air/water combination which is being tested everything else MUST be constant:-

bottle size, wheel type, surface, slope of surface etc.bottle size, wheel type, surface, slope of surface etc.

Children need to discuss the combinations possible, Children need to discuss the combinations possible,

we opted for 250ml increments, which gives each group 9we opted for 250ml increments, which gives each group 9

tests to complete, 27 if 3 repeated readings are taken!tests to complete, 27 if 3 repeated readings are taken!

The play session can be used to narrow this down andThe play session can be used to narrow this down and

give the children a good idea of the combinations thatgive the children a good idea of the combinations that

provide greatest propulsion.provide greatest propulsion.

( Which is bottle being ½ to ¾ full of water)( Which is bottle being ½ to ¾ full of water)

Volume of water(ml)

Volume of air (ml)

2000 0

1750 250

1500 500

1250 750

1000 1000

750 1250

500 1500

250 1750

0 2000

ResultsResults

Which volume of water propelled the car the furthest?

0

2

4

6

8

10

0 500 1000 1500 2000 2500

Volume of water (ml)

Dis

tance

tra

vele

d (m

)

The results can be recorded in an Excel spreadsheet which the children can design themselves or use the one provided (it is pre-populated with genuine test data to give an idea of expected results). More able/older children will be able to use the chart wizard feature to produce a line graph (XY Scatter and select points joined) or again the spreadsheet provided will allow children to enter their data and the graph will automatically plot. Data is only entered on the graph when a new cell is selected. The resulting graph is shown below. Click on the graph for the datasheet and change the data to see the graph change.

ConclusionConclusion

Children present their results and conclusions back to the Children present their results and conclusions back to the class this is done with reference to the ICT data table and class this is done with reference to the ICT data table and chart. Are there any changes they would like to make? chart. Are there any changes they would like to make? Was it fair? Were repeat readings taken? Was the DT Was it fair? Were repeat readings taken? Was the DT design and construction robust enough to withstand the design and construction robust enough to withstand the forces produced? The use of digital images and video forces produced? The use of digital images and video enhance these presentations and a short PowerPoint enhance these presentations and a short PowerPoint could also be included. But the question that must be could also be included. But the question that must be answered is……….What was the water/air ratio which answered is……….What was the water/air ratio which propelled the rocket car the furthest? And……….. WHY?propelled the rocket car the furthest? And……….. WHY?

ExtensionsExtensions

Children can get carried away with this project and often provide their own Children can get carried away with this project and often provide their own questions and this results in spin off experimentation without teacher questions and this results in spin off experimentation without teacher input. However possible planned extensions/differentiations are:-input. However possible planned extensions/differentiations are:-

To fine tune the ratios to find out exactly what water/air combination To fine tune the ratios to find out exactly what water/air combination between 1000 and 1250ml gives the greatest force – children use 50ml between 1000 and 1250ml gives the greatest force – children use 50ml (or less) increments and re-plot their tables and graphs.(or less) increments and re-plot their tables and graphs.

Use one water/air ratio and change another variable -wheel material or Use one water/air ratio and change another variable -wheel material or diameter, test track surface etc.diameter, test track surface etc.

Use one water/air ratio and change the size or style of the bottle, add Use one water/air ratio and change the size or style of the bottle, add spoilers to increase aerodynamics does it make any difference?spoilers to increase aerodynamics does it make any difference?

Keep an experimental diary containing sketches and photographs, Keep an experimental diary containing sketches and photographs, thoughts and hopes, the highs and lows, the modifications and thoughts and hopes, the highs and lows, the modifications and difficulties, the feeling of the team are they working well together?difficulties, the feeling of the team are they working well together?

Support materialSupport material

NASA website – loads of NASA website – loads of rocket based activities and rocket based activities and teachers guidesteachers guides

(http://(http://exploration.grc.nasa.gov/exploration.grc.nasa.gov/education/rocket/education/rocket/TRCRocket/TRCRocket/RocketActivitiesHome2.html)RocketActivitiesHome2.html)

Instructions on building a Instructions on building a balloon rocket car, a good balloon rocket car, a good weekend homework task for weekend homework task for all the family!all the family!

((http://www.life.uiuc.edu/http://www.life.uiuc.edu/boast1/sciencelessons/boast1/sciencelessons/rocketcar.htmrocketcar.htm))

Movie 1

Movie 2