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ESCAPE FROM THE CLASSROOM CONFERENCE

9 February 2013

Science Enquiry in your School Grounds

Key Stage 1 and 2

Georgina Cass, Derbyshire County Council - Environmental Studies Service

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Scientific Enquiry Outdoors

It is hoped that taking Science outdoors and developing a scientific enquiry process will:

• Excite and stimulate children’s curiosity about the world around them basing enquiry in real life, relatable situations.

• Give them the confidence to raise their own questions and use techniques, skills and equipment to investigate and find answers their own questions

• Continue to develop ideas starting from their current level of understanding and be prepared to test, discuss and justify their ideas and modify them based on evidence and experience.

• Develop and evaluate their ideas using evidence, experimentation and modelling in a real life familiar setting

• Give pupils responsibility for their learning outside the confines of a classroom

• Develop team work, speaking and listening skills

• Enable engagement of pupils with different learning styles and allow pupils of all abilities to succeed and enjoy.

These ideas are based on the following principles:

• Scientific enquiry and questioning is the basis. The activities sometimes give a theme or concept but should, wherever possible, allow the investigative process and enquiry question to be child centred, child directed and child led based on their current level of understanding and interest and allow them to extend and build on this.

• Use basic equipment that is either free, inexpensive, easily available and does not take a long time to set up, prepare or pack away.

• Make use of your outdoors as a scientific laboratory and learning space but without the need for well-developed or particularly elaborate grounds with lots of different areas, habitats or features – i.e. uses the basics well.

Contents: Page

Planning an enquiry 3

Key Stage 1:

• Curriculum links

• Physical processes outdoors(light and sound, electricity, forces and motion)

• Materials and their properties outdoors (grouping materials, testing materials, changing materials)

• Life processes and living things outdoors (Green plants, grounds exploration)-

4 5 - 6 7 - 8 9

Key Stage 2:

• Curriculum links

• Life Processes and living things outdoors (my grounds, circulation, growth, nutrition, adaptation, micro-organisms)

• Materials and their properties outdoors (designing your grounds, testing materials, changing materials, separating mixtures)

• Physical Processes outdoors (circuits, forces and motion, the earth and beyond)

• Outdoor composting science resources from Little Rotters

10 11 - 12 13 - 14 15 16 - 19

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PLANNING AN ENQUIRY

Encourage your children to share their ideas and questions. Developing a scientific enquiring mind requires your children to feel confident and be willing to experiment and try. Emphasise that they won’t always get a ‘final answer’ and encourage an environment where they can share their ideas without the fear of being ‘wrong’. All the great scientists had to ‘have a go’ and be prepared to experiment. A good scientific enquiry should start with

• An idea or question

• Test it

• Discuss it

• Reflect on it

• Develop it

• Challenge it

• Justify it

• Modify it

• Use evidence and experience

Checking your test - is it fair? A useful flow chart taken from Nuffield Primary Science In-Service Pack

Enquiry Principles 1. What ideas or question are

we investigating, testing, measuring or observing?

2. What predictions can we make?

3. What information do we need to use to answer the question?

4. What evidence do we need to collect? What equipment and materials do we need to use?

5. How can we make the test fair? Remember to change one thing at a time if you can.

6. Think about any dangers, risks or ways we need to keep safe.

7. How can we record our observations and measurements

8. Do we need to repeat and check our observations and measurements

9. What patterns, comparisons and conclusions can we make? How can we explain these?

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Key Stage 1 – Scientific Enquiry in your school grounds Key Stage 1 Science Programme of Study The activities and ideas suggested link with the following: Sc1 – Scientific Enquiry

• Ideas and evidence in Science – 1

• Investigative Skills – 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, 2i, 2j Sc2 – Life Processes and living things

• Green Plants - 3a, 3c

• Variation and Classification - 4b

• Living things in their environment - 5a, 5b, 5c Sc3 – Materials and their properties

• Grouping materials – 1a, 1b, 1c, 1d

• Changing materials – 2b Sc4 – Physical processes

• Electricity – 1a, 1b, 1c

• Forces and motion – 2a, 2b, 2c

• Light and Sound – 3a, 3b, 3c, 3d Cross Curricular links to: Literacy/English, Mathematics/Numeracy, Design Technology, Geography, ICT, Sustainable Schools (Buildings and Grounds, Inclusion and Participation), Learning Outside the classroom manifesto etc.

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Sc4 – PHYSICAL PROCESSES ENQUIRIES

LIGHT AND SOUND Making and detecting sounds Sit out in the grounds with eyes closed. Focus carefully on the sounds that can be heard for two or three minutes. Make a list of different sources of sound. How do we hear? Where does the sound travel to and from? In small groups jot these ideas down either in picture form or in written form. Discuss together questions they’d like to ask about the sources and types of sound. E.g. where do the sounds come from, which are near, far, loud, quiet etc. Use some sound making devices close to and further away from the children e.g. ring tone on a phone, drum, xylophone etc. What do they notice about the sound? What ideas do they want to put forwards? How can they test this? How will they measure it? How will they record what they have found out? Support the children to plan out their investigation, what equipment will they need. Think carefully about how to make it a fair test. For example – Sounds get fainter as you travel away from the source. Use a map of the school grounds. Plot on where the source of sound is. Predict how far away you will be able to hear the noise. Spread pupils around the grounds some close, some far. Make the sound and see who can hear it. You may need to phone each other to check if the noise was heard if the distances are large! If using a drum or instrument think about whether you are hitting it hard or soft. Think about how the sound is made e.g. a vibration. Do you need to be blindfolded or close eyes so you are definitely hearing sound not looking at when the sound is made? Which instruments make the noise travel far or not so far? Plot on the map how far away you could hear the sounds. What conclusions can you draw? Light and dark Where does light come from? Do a brainstorm to establish current understanding and ideas. This could be done as a group with one person recording or individually in written or picture form. Think about sun, moon, stars, torch, electric light bulbs, mobile phone screens, LEDs in shoes. What makes things dark? (The absence of light) How could you work out where the darkest part of the school grounds is during the day time? How would you measure this? You could use a simple datalogger with a light meter on it or it could be done by careful observation. Can the pupils predict and then check. Under the trees? In the compost bin? In the centre of the playground? In the shadow of the school building? Etc.

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ELECTRICTY Traditionally teaching on electricity is done indoors. Encourage the children to think about electricity outdoors. Is there anything in the grounds that uses electricity or is linked to electricity? Might be gardening tools by grounds maintenance staff? Pylons and wires that are visible? Safety lighting? Specific toys? What is special about electricity outside i.e. it has to be waterproof and weather proof to be safe. Make a simple circuit with a battery, wires and bulbs. Have a break in the circuit and see what in the grounds can be connected to close the circuit and make the bulb light up. E.g. clipping the wires onto the climbing frame, fence, wooden seats, stick. Encourage the pupils to experiment and try out different things and record which work and which don’t. Discuss together what the things that work had in common. If you have a simple energy kit or simple solar panel think about where solar lights could be installed. Make a simple circuit and think about where a solar light might be useful outside. Get them to design their own and see if it works. Or where a windmill powered motor might best be placed. Think about how a buzzer circuit might be useful outdoors. Encourage children to get involved in understanding how any other outdoor circuits work. E.g. sensor security lights, a web cam into a bird box etc.

FORCES AND MOTION Car challenge! For this activity you can either challenge the pupils to work in groups and use ready made car toys or better still challenge them to make their own using construction kits e.g. kinnex, or lego. The initial challenge is to make a vehicle that will travel across a smooth area e.g. paved or smooth tarmac area. What do they do to make it ‘go’? Ensure the pupils describe how they make it move e.g. a force has to be used (push) or possibly pull? If the cars spin what could they do about this? Why do they change direction? Find or build a ramp area. The challenge is to see which group’s vehicle goes the furthest and/or fastest. This can be measured using tape measures, stop watches and recorded as required. Allow opportunity to change aspects of the design e.g. add or take away weights and wheels. How did this improve performance? Why? Let the pupils decide whether they can give the cars a push to get started! Try on different kinds of surface. How does this affect how the cars move? E.g. on grass, rough tarmac, sand areas, soil etc.

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Sc3 – MATERIALS AND THEIR PROPERTIES ENQUIRIES

GROUPING MATERIALS Materials Collection Provide pupils with the range of your grounds and ask them to collect items and bring them back. Place some hoops on the ground and allow the pupils to sort and group the materials and items depending on their properties. You can spend quite a lot of time grouping and re-grouping. Sometimes best to jot down with chalk or scrap paper and take photographs of the different ways of grouping. E.g. natural or made by people – shiny, dull, rough, hard, soft etc. Ask questions to draw out how they decided on these properties – what senses did they use and why. Use these materials to develop other tests. E.g. what floats and sinks – make predictions and test them. Work out how to record this. Build a bridge Use a water tray or sand tray make a variety of materials available make sure that the children have to specifically ask for certain things so they have opportunity to select materials e.g. wooden sticks, straws, duplo, lego, cardboard, string, sellotape, blu tak etc. The challenge is to build a bridge over a certain distance that will support something – weights, a toy car, animal figures etc. Let them work together and then test. Discuss which materials worked best and why – what properties did they have that helped them to work best for this particular use. Bounce a Ball Provide a variety of ball types – sponge, basketballs, football, plastic balls, tennis balls etc. Develop an investigation that tests which balls bounce best on which surface. Allow the children to select which surfaces they will try – e.g. playground, grass, soil, pavers, gravel etc. And how they will measure the bounce and make sure this is a fair test. How will they record this? Can provide a frame or chart for writing it down. How will they observe this and check and compare. What have they found out about different surfaces? What properties do the surfaces have? What properties do the balls have? What games might they be most suitable for? Postman or Santa’s delivery This investigates which materials are strongest. Provide different kinds of wrapping materials – e.g. wrapping paper, silver foil, crepe paper, tissue paper, cardboard, newspaper etc. Pupils are to wrap a number of parcels which will then be tested. Use the comparison of a package making it through the delivery process – e.g. through the sorting office – being passed around, in the postman’s bag or bike. Or like Santa trying to make sure that the presents arrive in one piece. Throw the parcels between the pupils and see which wrapping lasts the most passes. Put the parcels into a bike basket or into a pull along trolley and ride around the grounds and see which packages are most intact after 2 minutes, 5 minutes, 10 minutes Put the parcels on a sledge and drag them down a hill or across the field and see which of Santa’s parcels last longest.

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My waterproof hat / umbrella Allow pupils to use natural and unnatural materials to develop and construct their own waterproof hat or umbrella. Test it to see how many drops of water it takes before it soaks through. What properties do the best materials have that make them most suitable for the job.

CHANGING MATERIALS Bread making outdoors If you have someone qualified or confident to have a campfire or barbeque or are running Forest School sessions think about doing heating and cooling work outdoors. Pupils love to experiment with outdoor heating and cooking e.g. how to build a small campfire, what materials to use, how to manage it safely, then simple cooking on an outdoor fire e.g. how bread changes, how marshmallows melt, how popcorn pops and importantly cooling and extinguishing the fire and how the materials have changed in the process e.g. charcoal from the wood fuel, ash etc.

How to Cook Bannock on a Campfire – Bread on a Stick Taken from http://www.paddlinglight.com/articles/tutorial/how-to-cook-bannock-on-a-stick-campfire-bread/ Preparation of the Bread Dough At home mix all the dry ingredients into a plastic bag. You can substitute or remove some of the ingredients as you wish. Traditional bannock was just flour and water. In my recipe, baking powder makes the bread fluffy, salt brings out the flavours, powdered milk allows the bread to brown and butter adds flavour. You can add anything to the base to change the flavours. If you want a sweet bread add cinnamon and sugar. In the mood for something cheesy, then toss in some chunks of cheese. 1 cup flour 1 tsp baking powder 1/4 tsp salt 2 tbsp powdered milk 1 tbsp oil or butter In camp, mix in the oil or butter (ghee). Add water slowly until you create dough the consistency of play-doh. You want a firm dough that isn’t sticky. If you use the baking powder, set the dough aside to let it rise. Full details including gathering and preparing the stick, wrapping the bannock dough onto the stick, where in the fire to cook the bread and how to cook it and remove and eat it is available on the website listed above including videos and pictures.

Natural and outdoor materials Don’t forget to use outdoor resources when you are doing changing materials enquiries. E.g. what happens when you squash or press flowers and berries? What happens when you bend different kinds of wood (e.g. some are very flexible e.g. willow and some are brittle and snap – can depend if they are green wood and fresh with sap in or dead wood and dry). What happens when you twist the vegetables when you are digging them up? Stretch the football nets or so on. Include items to see what happens when they freeze and cool e.g. pebbles, sticks, grass and so on.

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Sc2 LIFE PROCESSES AND LIVING THINGS

GREEN PLANTS What do plants need to grow? Set up an enquiry using seeds collected from the grounds or from wildflower seeds or using cress, vegetable seeds etc. Allow the pupils to decide what they will grow, where it will grow and what they will be given e.g. soil, no soil, water, no water, light, no light, outdoors, indoors and allow them to experiment and record and monitor over a relatively long period.

VARIATION AND CLASSIFICATION AND

LIVING THINGS IN THEIR ENVIRONMENT What’s in our grounds? Introduce a range of equipment for sampling and observing e.g. magnifying glasses, sweep nets, pond nets, magnifying jars. Identification charts etc. Ask the pupils what they think might live in the grounds, what kinds of animals and plants, what might live where, what animals they will be able to see, what animals might only leave ‘evidence’ e.g. rabbit droppings? Bird poo? What animals they might be able to gather and observe. Choose different areas of the school grounds – e.g. compost bin, flower bed, pond possibly, woodland area, wildflower area, trees, hedges, field, playground etc. Encourage the pupils to select the right equipment for sampling and observing. Sample, observe and handle the areas sensitively and ensure that any living things are returned to their environment. Discuss ways that they can record what they find e.g. photographs, sketches, named lists etc. When the class has gathered all of its observations and evidence either use photographs, pictures or words to sort them into groups with things that are similar (e.g. plants, animals, insects, birds) or those that are different (things that can survive underwater, above ground, under the ground etc.) Extend by asking if they can think of any other enquiries or questions. E.g. which area of the grounds had the most variety of living things? Why do you think this is? Can we prove that? How could we improve the range of living things that live in our grounds etc.?

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Key Stage 2 – Scientific Enquiry in your school grounds Key Stage 2 Science Programme of Study The activities and ideas suggested link with the following: Sc1 – Scientific Enquiry

• Ideas and evidence in Science – 1a, 1b

• Investigative skills – 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h, 2i, 2j, 2k, 2l, 2m Sc2 – Life Processes and living things

• Life processes – 1a, 1b, 1c

• Humans and other animals – 2c, 2d

• Green plants – 3a, 3b, 3c

• Living things in their environment – 5a, 5b, 5c

• Micro-organisms – 5f Sc3 – Materials and their properties

• Grouping and classifying materials – 1a

• Changing materials – 2b, 2c, 2d, 2e, 2g

• Separating mixtures of materials – 3a, 3b, 3c, 3e Sc4 – Physical processes

• Electricity simple circuits – 1a

• Forces and motion – 2c

• The Earth and beyond – 4b Breadth of Study – 1a, 1c, 1d

o Communication – 2a, 2b Cross Curricular links to: Literacy/English, Mathematics/Numeracy, Design Technology, Geography, ICT, Sustainable Schools (Buildings and Grounds, Inclusion and Participation), Learning Outside the classroom manifesto etc.

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Sc2 LIFE PROCESSES AND LIVING THINGS

LIFE PROCESSES In our grounds I’ve noticed….. how can I check that I’m right? Set up and undertake a detailed or long term enquiry using the different kinds of spaces, habitats or environments in and around your grounds. Ask the pupils to record what kinds of ‘areas’ there are in the grounds and what they know about the plants and animals in these areas. For example ‘the field’, ‘the playground’, ‘the pond’, ‘the wildlife area’, ‘the vegetable plot’, ‘the flower beds’ etc. Are there certain plants or animals in different areas? What do they want to find out or how can they test their ideas. Examples:

• There are more kinds of plants and animals in the pond than in the field area.

• The plants in the shady areas grow more slowly than those in the sunny areas

• The trees in the windy part of the field lose their leaves earlier than those in the courtyard area.

• There are a greater quantity of animals in the hedge than in the field

• More pond animals live at the edge of the pond than in the middle or at the bottom of the pond than the top.

• It is hotter in the compost bin than in the shed

• There are more different kinds of insects in the woodland area than in the flower beds.

• There are more different kinds of plants in the wildflower garden than the planted flower beds

• There are more birds in our grounds in the summer than the winter. Think carefully about what needs to be measured to check these statements and ideas. What techniques might be used and what could be measured. These could include

• Pond dipping at different times of year or in different areas

• Sampling – using grass sweep nets, quadrants or hoops

• Measuring the height or girth of the trees or plants with tape measures, rulers etc.

• Counting up the number of animals plants

• Recording observations or recording using photography

• Looking at what specific species are doing at specific times of year – e.g. birds, trees, insects, pond creatures, plants, flowers etc. – bring out common processes e.g. growing, eating (nutrition) and reproducing.

Think about recording methods:

• Writing up observations or labelling sketches and pictures

• Tally charts and tables

• Graphs – could be temporary unifix graphs if required

HUMANS AND OTHER ANIMALS Circulation - Pump it up Having learnt about how the heart acts as a pump works. Teach pupils how to read a pulse. Take a resting pulse over 1 minute. Read it three or four times and discuss taking an average and link to work in maths.

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Make predictions about what happens to happens to heart rate when you exercise - does it increase, decrease, is everyone the same? Why is it important to raise your heart rate? Do you breathe more in a certain time period? Why? Work out a way to test these ideas and how you will record this – might need a stop watch, table or chart, tape measure for a particular distance. Do a number of star jumps, walk a certain distance for a certain time – then read heart rate. Count number of breaths. Do you feel different? Look different? Use observations and ‘feelings’ as well as measurable factors. Increase speed, time or number of exercises done – measure etc. This could be extended into a wider school ‘healthy living’ research or even into working with families at home to measure and think about differences or compare improvements over a term as they get fitter?

GREEN PLANTS Growth and nutrition Set up an enquiry using seeds collected from the grounds or from wildflower seeds or using cress, vegetable seeds etc. Use the ‘framework’ to establish ideas and questions to investigate. Allow the pupils to decide what they will grow, where it will grow and what they will provide for the plants. What does the ‘control’ get? What factors do they change elsewhere? Will they provide e.g. soil, no soil, water, no water, light, no light, outdoors, indoors, cold or warm areas. Consider removing roots and seeing what happens, taking leaves off etc. Allow them to experiment, observe and record and monitor over a relatively long period.

LIVING THINGS IN THEIR ENVIRONMENT Adaptation - Super seeds Use the plants or trees in your environment to carry out an investigation. How do the plants spread their seeds? Which plant produces most seeds? Which seeds are most likely be spread over a wide distance? Which seeds are most likely to be protected and not get eaten or damaged before they grow? This works particularly well with common tree seeds which might be in your grounds or nearby e.g. sycamore helicopters comparing with conkers from a Horse Chestnut. They can count how many seeds different trees produce. How they fall, travel, their size, weight, protection and explain how they work in different ways to the same end. Pupils can think up tests that compare the two and try and explain how the different features are suited to the environment the trees live in. Micro– organisms. Make your own compost bin and investigate decomposition rates. Three experiments and enquiries all taken from the ‘Little Rotters Composting Club’ http://www.littlerotters.org.uk/. All resources at the end of this handout.

• Rotting Rates

• Banana Breakdown

• Mini Composter

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Sc3 – MATERIALS AND THEIR PROPERTIES ENQUIRIES

GROUPING AND CLASSIFYING MATERIALS

Science, grounds development and money! Think carefully about developments in your grounds – new play equipment, planting, vegetable beds, new turf etc. Use scientific enquiry to allow pupils to work out what materials, items or species would be best for the job. E.g. If pupils are setting up their own garden and they want to know which brand of seeds are most economical and successful. Design an investigation to carry this out. If you are buying a new bench what material would be best- think about rotting, rusting, risk of graffiti, burning – small samples of materials such as wood, plastic, metal etc. could be used and is a useful way of starting to discuss what is safe to test e.g. not burning plastic! If you are putting seed down for a new pitch – what is the most hard wearing grass seed mix? How can this be tested? What other factors do they need to consider. Any of these investigations could lead to a literacy based write up – e.g. for a magazine giving a ‘star’ rating or ‘value for money’ reply. Which material? Look at the different materials that things are made out of around your grounds. Test them for how hard, how strong, how flexible, how magnetic etc. What material would you use for a climbing frame? Making a vegetable bed? Making a safety surface? Challenge the pupils to test and explain their choices. Breakables! Devise a test to see what surface would be best underneath a play area. Drop a ‘breakable’ from a specific height and see what impact it has. Obviously don’t choose anything dangerous (e.g. glass) but something that will crack on heavy impact. Eggs are really messy unless you hard boil them first! Chocolate Eggs or crème eggs are quite good for this and good fun. Although a ‘slot together’ toy might do the job as well. Think about making the test fair (same height, force etc.) and trying out different surfaces. How can the results be measured and recorded.

CHANGING MATERIALS

Bread making outdoors See guidelines and ideas in Key Stage 1 section. At Key Stage 2 the pupils can take the lead themselves more and manage the fire if suitably trained and confident staff and procedures are in place. Natural and outdoor materials Don’t forget to use outdoor resources when you are doing changing materials enquiries. E.g. what happens when you squash or press flowers and berries? What happens when you bend different kinds of wood (e.g. some are very flexible e.g. willow and some are brittle and snap – can depend if they are green wood and fresh with sap in or dead wood and dry). What happens when you twist the vegetables when you are digging them up? Stretch the

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football nets or so on. Include items to see what happens when they freeze and cool e.g. pebbles, sticks, grass and so on. Evaporation and condensation – what makes puddles disappear? Draw around a puddle on the playground at the beginning of the day with chalk, continue to go outside and draw around it at different times of the day (hopefully on a dry day so no further rain is added!). Record observations using photography, sketches or measurements.

SEPARATING MIXTURES OF MATERIALS Sewage sludge Have a tank of water and a wide range of every day items. Go through a ‘day’ and think about what goes into your waste water supply different parts of the day. E.g. soap, shower gel, toothpaste, food (cornflakes, crumbs) wash powder, salt, sugar, toilet paper, poo, pebbles from the roads, mud, soil etc. Challenge pupils to set up their own sewage treatment works in the grounds and try and clean the water and separate the mixture. Use sieves, colander, fabric pieces, kitchen roll, filter paper, funnels – see whose is the cleanest. Think about what things are still in there e.g. dissolved items – how could these be removed?

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Sc4 – PHYSICAL PROCESSES ENQUIRIES ELECTRICITY

Circuits and batteries Challenge pupils to make a circuit for an outdoor light. How would they make it waterproof? If you have a solar panel or solar lights look at how the solar panel acts as the ‘battery’ in the circuit. Set up an enquiry that tests the best position to place a solar light or design a circuit for a solar light and test if it works.

FORCES AND MOTION Friction and flow Using a set of toy cars and a smooth surface area (on a gentle slope) set up an experiment that tests friction. This could involve measuring the distance of a hairdryer or fan from the car which prevents it from moving. Test out what difference different items on the surface make to the friction e.g. sand on the surface, gravel, soil, oil, butter etc. Can be linked to work on railways, tramways, cars etc. Flying people Use figures and characters, string and a variety of different materials and resources. Pupils are challenged to design a parachute for their figure which maximises air resistance and therefore slows the drop to the ground. Test these from dropping them from the top of a climbing frame or out of window if safe to do so!

THE EARTH AND BEYOND

Periodic changes – shadows and the sun How can pupils prove that the position of the sun appears to change during the day? Use a rounders post, netball post, stick in a vertical position somewhere in the grounds where it won’t get moved all day and won’t go into the shade. Draw around the shadow with chalk and mark down the time, continue to go outside and repeat at different times. Look at the length of the shadow and position of the shadow and work out what that tells you about the sun e.g. when it is overhead or to the east, west etc. It can be useful to link this to mathematical work e.g. designing, measuring and drawing up a sundial somewhere in the grounds. Survival shadows A simple technique for working out direction if you’re ever lost and don’t have a map or compass! You do need to know which hemisphere you are in! Taken from http://www.compassdude.com/no-compass.shtml

The sun moves across the sky from east to west and its shadow gradually changes in length which is what makes this direction finding method work. Clear a flat area of dirt or sand. Grass will work, but not as well.

• Find a stick about 2 or 3 feet long and stick poke it into the ground so it stands up.

• Get another small stick or pebble and place it exactly on the end of the shadow line.

• Eat a trail bar or relax for a half hour.

• Place another stick or pebble at the end of the new shadow. If you have time, wait another 1/2 hour and repeat.

• The line between the two pebbles runs east-west direction with the first mark being west and the second being east.

• If you are in the northern hemisphere, North direction is perpendicular to the east-west line heading away from the sun. It's South down under.

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