1. © OCR 2012

2. Battling ideas Student Sheets A skills development activity for GCSE

3. © OCR 2012 SS1Which number (consumable)Cut into A5 sheets SS2Battling ideas (consumable) SS3Battling ideas exam practice (reusable) SS4Marking guide (reusable)For teacher use but can be used by students for self/peer assessment Sheet number Title Notes Contents

4. © OCR 2012 SS 1OCR SKILLUP : BATTLING IDEAS Which number? Round 2PredictionObservation 1 st 1 2 nd 3 rd 4 th 5 th 6 th rule linking numbers: Round 1PredictionObservation 1 st 1 2 nd 3 rd 4 th 5 th SS 1OCR SKILLUP : BATTLING IDEAS Which number? Round 2PredictionObservation 1 st 1 2 nd 3 rd 4 th 5 th 6 th rule linking numbers: Round 1PredictionObservation 1 st 1 2 nd 3 rd 4 th 5 th

5. © OCR 2012 Battling ideas OCR SKILLUP : BATTLING IDEAS SS2 Round Does the observation match their prediction? How confident are you that the explanation is correct? 1st 2nd 3rd 4th 5th ***** = very confident *= not at all confident Contest 1 The idea that I support is… His explanation is that… ● What makes one explanation more convincing than another? ● Did you change your mind when there was more evidence for a different explanation? Give an example of when this happened. Round Does the observation match their prediction? How confident are you that the explanation is correct? 1st 2nd 3rd 4th 5th ***** = very confident *= not at all confident Contest 2 The idea that I support is… His explanation is that…

6. © OCR 2012 Wegener’s theory Time ●Explain why Wegener’s theory of continental drift was not accepted by scientists but the theory of plate tectonics now is. ●Explain why it may need to be revised in the future. Number of scientists who support the Theory. Almost noneFewSomeMost 1930: Death of Alfred Wegener Theories Wegener’s theory of continental drift Revised theory of plate tectonics. Observations Alfred Wegener noticed that the Earth’s continents fitted together like a jigsaw puzzle. His explanation for this was that they once had been joined but then slowly moved apart. He called his theory ‘continental drift’. During his lifetime he collected evidence for this theory but not enough to convince other scientists. OCR SKILLUP : BATTLING IDEAS SS3 Wegener finds the same fossils in Africa and South America and predicts that fossils will match on other continents. Wegener finds fossil matches between several other continents. Mid ocean ridges were discovered. Scientists suggested that the ocean floor spreads outwards from these ridges. This pushes the continents apart as Wegener predicted. Magnetic stripes in the sea floor were mapped. They supported the prediction that rocks form at the ridges and move away as the sea floor spreads. Wegener notices Africa and South America fit like jigsaw pieces and predicts that they were once joined.

7. © OCR 2012 Wegener’s theory : Marking Guide Thinking scientifically General criteria Wegener’s theory Typical student response Low demand Recognise that science explanations are provisional because they only explain the current evidence ●Continental drift was not accepted because Wegener did not have enough evidence to convince other scientists but plate tectonics is accepted because there is lots of evidence. (1-2 marks) Standard demand Recognise that science explanations are provisional but more convincing if predictions can be made and subsequently confirmed As above plus: ●The theory of plate tectonics was accepted as more observations made by many different scientists matched the predictions made by this theory e.g. the observation that the sea floor is spreading backs up Wegener’s predictions that the continents are moving apart. ●Support for the theory grew as predictions based on it turned out to be correct. (3-4 marks) High demand Recognise that confidence increases in provisional scientific explanations if observations match predictions but this does not prove the explanation is correct As above plus: ●Continental drift was not accepted because Wegener could not explain why the continents were moving. ●Plate tectonics is supported because scientists have evidence that the Earth is divided into plates which are moving. ●In the future there may observations that cannot be explained by the theory and then the it may need to be modified in order to explain these. (5-6 marks) OCR SKILLUP : WHAT’S THE CONCLUSION? SS9 OCR SKILLUP : BATTLING IDEAS SS4

8. © OCR 2012 Skillup activities from OCR, created by the upd8 team – anything you'd want to add about your courses, or the Developing Student Skills Poster. Picture Student sheet Credit Picture credits All images purchased from Dreamstime or iStock 4450374067 1/12