Essex Primary SCITT

1. Essex Primary SCITT Primary Science Course Lecture 4

2. Objectives for the day • Develop trainees’ knowledge and understanding of the concept of forces, including: • Magnetic • Friction, including air resistance • Gravitational • Electrical • Consider elements of an effective science lesson plan. • Develop trainees’ knowledge and understanding of the scientific enquiry skills of recording, including the use of tables; • Develop trainees’ ability to plan and teach scientific activities, including applying scientific knowledge to solve a problem.

3. What have we learnt so far?

4. Pedagogy • Motivating children and developing curiosity • Children’s development in science • Risk assessment • Selecting appropriate resources • Pre-assessment • Use of talk partners • Assessing whilst teaching • Mini-plenaries – notable impact • Use of IT to extend learning

5. Children’s Development in Science • Development of observation skills • Development of questioning skills • Development of process skills • Dimensions of Progress • From description to explanation • From ‘small’ to ‘big’ ideas • From personal to shared ideas

6. A constructivist view of learning Based on the work of Piaget (maturation) and Vygotsky (zone of proximal development) • A child’s head is not empty • There is an interaction between pre-existing ideas and new experiences and phenomena • Children attempt to make sense of new experiences and phenomena by constructing meaning • This is a continuous and active process • To learn, therefore, children not only have to assimilate new concepts but also develop, modify and change existing ones

8. What is a force? Give as many real world uses of the word Force as you can think of.

9. Give as many real world uses of the word Forceas you can think of

10. What do children think the word force means? • My mother forces me to tidy the room when I don’t want to. • A force is when you are made to do something. • Forces are big and strong. • Forces are power and energy. • When it snows and it’s cold and there’s snow everywhere you have to force your way through. • I’m not sure what force means but there’s an air force. It’s got a blue uniform. There’s also brute force. • Force is gravity and wind.

11. True or False? • The weight of an object depends on how much stuff it is made from. • A stiletto heel will make a deeper hole in a wooden floor than a wider heel, when worn by the same person. • Crumpled paper falls faster because it weighs more than uncrumpled paper. • When you stretch a spring down and let go, gravity makes it pull back up. • Magnets will pull together or push apart depending on which way round the poles are.

12. We weigh less on the moon than we would on earth. • A shark has a streamlined shape in order to reduce air resistance. • Friction can be both helpful and unhelpful. • A knot of plastic string is easier to untie than natural string because the plastic has a smooth surface so there is less friction. • Unequal forces can change the shape, speed and/or direction of an object. • A still object no longer has any forces working on it. • To calculate the speed of an object you also need to know how long it has taken to do a journey and how heavy it is.

13. What do forces do? • Make stationary objects move. • Make moving objects speed up. • Make moving objects slow down. • Make moving objects stop. • Make moving objects change direction. • Change the shape of objects.

14. Two characteristics of forces • Forces can be thought of as pushes and pulls. • Pushes and pulls can create change: in the size of an object and/or the direction of movement. • Whenever there is any change to the speed, direction of movement or shape of an object it is because forces are acting on it.

15. Magnets and Magnetism What do I know about magnets and magnetism?

16. NC – Forces and Magnets LKS2 • Year 3 • compare how things move on different surfaces • notice that some forces need contact between two objects, but magnetic forces can act at a distance • observe how magnets attract or repel each other and attract some materials and not others • compare and group together a variety of everyday materials on the basis of whether they are attracted to a magnet, and identify some magnetic materials • describe magnets as having two poles • predict whether two magnets will attract or repel each other, depending on which poles are facing.

17. Magnetic Poles The earth is a very weak magnet and has a magnetic field. A compass points towards magnetic north so that we can find our direction. Magnetic north is not at the North pole but at a point in northern Canada.

18. Have 2 ends called poles, N and S. • Opposite poles attract, like poles repel. • Allowed to hang freely the N pole faces north. • A permanent magnet is a piece of metal that has been magnetized. • Only a few metals can be strongly magnetized and only some of these stay magnetised for any time. • Most permanent magnets are made of iron, often combined with nickel and cobalt. Magnets

19. Caused by the behaviour of electrons that remain in orbit in their atoms. They spin in a certain direction causing a magnetic force. If most of the atoms in a piece of metal are aligned so that the spins are in the same direction it is said to be magnetized. This can be induced by stroking a piece of iron with a magnet, in one direction. Magnetism

20. EYFS • Be a science detective – find 5 things that are magnetic/non-magnetic. KS1 • Sort and classify materials • Investigate/explore – Are all metals magnetic? KS2 • Describe some uses of magnets. • Investigate - Are round magnets stronger than bar magnets? • Is it true – the bigger the magnet the stronger it is? Magnets & Magnetism Activities

21. Children’s questions Children play with magnets. They ask … • Where do you get magnets? • Is the big one strongest? • Why is the red end better than the blue? • Where can you get magnets? • Are horseshoe or bar magnets the best? Which of these questions could lead to scientific activity?

22. Questioning Progression Early stages • Asking a variety of questions – investigable and non-investigable. • Discussing how to answer questions and which ones they can investigate themselves. Later stages • Discussing how different kinds of questions can be answered. • Recognising a difference between investigable questions and those that cannot be answered by scientific enquiry. • Clarifying questions by identifying what to change and what to observe or measure.

23. Exploring magnets Children explore how to test the strength of magnets • Find 3 ways to test the strength of magnets.

24. Helping children learn about forces • Read the article ‘Wearing Forces Spectacles’. • What are the key ideas suggested in the article that makes it easier for children to learn about forces?

25. Measuring forces • Mass (what is often called weight) is measured in grams and kilograms. • Forces are measured in Newtons. • On Earth gravity will pull on a 1Kg bag of sugar with a force of approximately 10 Newtons. • The ‘weight’ of any object is the amount of pulling force that the Earth exerts on that object.

26. Teaching children how to use a force-meter I • Remind children that forces are pushes and pulls. Ask them to turn to a partner, grasp each other by the and give a big pull. Next link little fingers and give a little pull. • Ask them to name units of measure e.g. cms, seconds, Kgms. Tell them that we use Newtons to measure the force of pushes and pulls. • Give out force meters. Allow children to try them out on objects in the class. Remind them to look at the scale. Then ask children to give a small pull on the force-meter of 2 Newtons or a larger pull of 10 Newtons.

27. Teaching children how to use a force-meter II • Look at different sized force-meters. Point out that some would be better for measuring small forces, some for larger. Work out what each small division is worth. • Tell children to try estimating forces, as they estimate length etc. Use one force-meter between two. One pupil holds the hook on the forcemeter the other says “Give me a pull of 6N.” • Link 2 different force-meters and help them recognise the force will be the same on each, but the springs will be stretched differently.

28. Mass, weight, force. • A bag of sugar has a mass of 1 Kg. That is the amount of material (matter) it contains. • In space it would be ‘weightless’, on Earth it would be pulled downwards by gravity with a force of about 10 Newtons. • The mass is constant so if somebody threw the bag of sugar across the spacecraft and it hit you on the head, it would hurt as much as if it were thrown at you on Earth!

29. Newton meters weighing sugar 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 • On Earth. • 1 Kg pulls with a force of 10 N. • In space. • 1 Kg pulls with a force of 0 N. 1 Kg 1 Kg

30. Types of forces • Friction, including air resistance • Gravitational • Magnetic • Electrical

31. Underlying principles of friction • The direction of friction is opposite that of movement or potential movement. • Friction can occur in the absence of movement e.g. a car parked on a hill. • Both surfaces in contact contribute to the magnitude of the frictional force. • Different surfaces oppose movement to different extents. Generally, the rougher the surface the greater the frictional force. • Friction tends to be used for solids. • Viscosity is used for liquids. • Air resistance is used for gases.

32. What is the best way to move a stone block to the top of the pyramid? Lesson Plan

33. Prediction or Hypothesis? Prediction • This is a statement about what may happen in the future based on previous knowledge. It is not a guess! • A bridge made of 1 piece of card holds 100g. A bridge made of 3 pieces of card holds 300g. Prediction a bridge made of 2 pieces of card holds 200g.

34. Hypothesis or Prediction? Hypothesis • This is a statement put forward to attempt to explain something. • The suggested explanation need not be correct, but it should be reasonable in terms of the evidence available and possible in terms of scientific concepts or principles. • When comparing 2 puddles and hypothesising on which will dry first what hypotheses could be made and what scientific principle could support them?

35. Gravitational force • Commonly referred to as gravity • Because the Earth is so massive, gravitational pull towards it is sufficient to be observed, whereas the attraction between smaller bodies may not be noticeable.

36. Gravitational force and friction • When an object begins falling to the ground it will accelerate. • When the object is no longer accelerating, but travelling at a constant velocity, the forces of air resistance and gravitational force are said to be balanced. This is its terminal velocity. • All objects would fall at the same speed if it were not for air resistance, as whatever their mass the rate of acceleration on Earth is the same for all objects.

37. Diagrammatic representation of forces • The size and direction of forces can be represented by arrows. The larger the arrow the larger the force.

38. Air resistance What type of parachute would give a parachutist the safest landing? Alternatively – make helicopters and vary the wing length

39. Air resistance • Air resistance increases with the speed of an object and the surface area of the object. • The molecules in the air rub against anything moving through them. Each molecule that is hit slows the speed of the object by a tiny amount. • Parachutes are designed to increase drag by presenting a large surface area. • Things that are required to move very fast are designed to reduce drag.

40. Our table of results for a fair test What we change What we measure Yellow post-it Green post-it

41. Using tables for recording • Make sure children understand what ‘table’ means in a science sense. • Teach them how to use them and understand the information on them. Time to land (Seconds) Why did they write (Seconds) in the time to land column? How many sizes were tested? Size of parachute 10x10 cms 5 If you tested another parachute where would you put the size? 20x20 cms 11 Where should you put the new timings you make? 30x30 cms 18

42. Repeat readings • Doing repeat readings gives us a better idea of the more likely result (not the right answer!). • If we had only done one reading how confident would we be that the result was reliable? • If we did one more test what do you think would be the most likely result?

43. Our table of results What we change What we measure Yellow post-it Green post-it 1st 2nd 3rd Mean

44. Evaluating results • We all carried out our tests sensibly. Why do you think we got different readings? • How much trust would you have in repeat readings that were / were not closely clustered? • How closely clustered were our readings? • How much trust do you have in our results?

45. Don’t know the answer to a child’s question? Ask the object! Elstgeest suggests we can ‘ask the object’ then do something to find out the answer. • You can ‘ask’ a parachute how quickly it will fall to ground. • You can ‘ask’ a toy car how far it will go after rolling down the slope. • You can ‘ask’ a shoe what force is needed to move it. • You can ‘ask’ a magnet how many paper clips it can pick up.

46. Upthrust • This is an upwards force. In a liquid, it can be measured by lowering a known weight on a Newton meter into it. The downwards force is reduced due to the upthrust of the liquid. • Upthrust also accounts for the fact that a skier does not sink into soft snow.

47. Children’s common misconceptions • Friction only occurs between solids and surfaces. Air and water resistance are also frictional forces. • Gravitational attraction only occurs on Earth. • If an object is not moving, there are no forces acting on it (when in fact the forces acting on it are balanced). • Gravity is less in water. Objects appear to weigh less in water than in air because the upward push of water is greater than the upward push of air. • Heavy objects fall through the air at the same speed as light objects unless the light objects are slowed more by air resistance.

48. Useful Internet sites This site has some interesting activities for KS2. • http://www.bbc.co.uk/schools/ks2bitesize/science/ The specific forces activities can be found at … • http://www.bbc.co.uk/schools/scienceclips/ages/8_9/friction.shtml • http://www.bbc.co.uk/schools/scienceclips/ages/7_8/magnets_springs.shtml

49. Science Task 4 • Plan and deliver a science activity with a focus on your range of questioning to encourage exploration, develop language and allow children to develop their own ideas and make links between ideas. • Consider the question types in the lecture and those on the website.

50. Question types • These fall into different categories depending on the reason for asking them. • Attention focusing • Comparison • Measuring and counting • Action • Problem posing