No. of students 6026 B. 45.1% Only 45.1% answered correctly. 3 Learnings

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1 Human body Science: Class 3 Kavitha thinks that the cooking gas in her house is leaking. Which of these helped her notice the leak? B C D C. 28.4% Only 45.1% answered correctly Students at this level know about gases and air. They also experience certain properties of gases in their day-to-day life, like odour of gases, pressure exerted by gases etc. It is an important safety skill to be able to detect cooking gas leakage at home, by identifying the odour of the leaking gas. We asked this question to check whether students understand that it is generally not possible to see a gas leakage and that the earliest warning of a gas leakage comes mainly from the smell of the leaking gas. Less than half the students chose the correct answer to this question. 28% selected eyes (Option C) as their answer. Possible reason for choosing : Students selecting this option might be thinking that when gas leaks it always makes sound. Possible reason for choosing C: Students selecting this option are probably thinking that they can see the leakage from the cylinder or the hose. It is also possible that students got confused by the use of the word notice which is generally used for seeing. Possible reason for choosing D: Students are probably making a random guess while choosing this option. It seems that students are trying to relate their experiences with gases to answer this question. Different gaseous substances may exhibit different properties and possibly students at this level carry the confusion that all gaseous substances have similar properties. However gases have their own individual properties; they may or may not be similar. Students may have heard some sound while gas is being released from a pressure cooker or a spray. Students are probably extending this everyday experience to conclude that every kind of gas release must be accompanied with a sound. Similarly seeing steam coming out of a pressure cooker might have led to the notion that a gas being released can be seen. It is important for children to know first that all gases are not the same and that they can have different properties. Second, they should understand that these properties can be exploited for different purposes. It will facilitate appreciation of other properties of gases at higher levels. Show examples of different properties of different gases to students. Illustrate these properties using different examples. lso mention that some gases have certain properties that other gases do not have. For example- Helium is a light gas that has a typical smell Carbon dioxide is a gas found in fizzy drinks D. 8.8% % Students can be given some balloons. Some of them are filled with air and some of them with helium gas. They have to identify the ones filled with helium gas. They should be able to apply the understanding that if the balloon filled with helium is released, it will go up whereas one filled with air will go up only if pushed up. Even if they do not know this and are able to observe certain balloons going up, they can then be shown that those balloons were filled with a different type of gas helium. B. 45.1% Lesson plans and activities for teaching children about gases and their properties. S

2 Properties of Matter Science: Class 3 Water is poured from a glass into an empty bottle. The only thing that changes, is the B taste. colour. C shape. D amount of water. D. 42.2%. 8.7% 6581 B. 5.2% Only 41.2% answered correctly Students at this level know elementary properties of solids, liquids and gases. We asked this question to check whether they appreciate that nothing but the shape changes when a liquid is transferred from one container to another. round 41% of students chose the correct option, C while around 42% of students chose the wrong option D. Possible reason for choosing and B: Very few students have selected these options and they are making a random guess. Possible reason for choosing D: Students selecting this option possibly carry the notion that amount of liquid depends upon the shape of the container. The question tries to test the idea of conservation of volume, that if a liquid is transferred from one container to another, its volume is conserved. The volume does not change. Since liquids take the shape of the container, what changes is the shape. However, students don t seem to appreciate this idea and say that amount changes. Students always see liquids in vessels and even see larger vessels holding more liquid compared to smaller ones. They might even be looking at height which looks higher in case of thin narrower vessels compared to thick shorter vessels, even though the actual amount might be the same. This kind of observations could be influencing the way they are thinking in this question. Since the second vessel is looking larger, they might be thinking that it will contain more water than the first one. They miss the fact that water is just being transferred and so the amount cannot change. C. 41.2% The best way to treat a misconception is to challenge the wrong notion students have. For the misconception found in this question, try out the following activity. Place a smaller glass completely filled with water and a bigger glass side by side on a table. Pour the water into the bigger glass and ask students whether the amount of water will change or not. There will be students who will say yes. sk them that if the water is more in the bigger glass, what will happen if it is poured in the smaller glass. They might say that it will overflow. Pour the water back into the smaller glass and they will see that the amount remains the same. nother idea is to illustrate the same using a third vessel. Pour water from the smaller vessel in the third vessel and mark the height. Now pour it back to the smaller vessel. Show the water being poured to the larger vessel. Then ask student whether the amount changed or not. They might say that it increased. sk them what would happen if the water was then poured in the third vessel whether it will be more than the initial mark or less. Pour it and let student observe the level. Will the amount of water change? Let s check! Water from both vessels rise to the same height in the measuring cylinder. Height Height S

3 Living Organisms - Form & Function Science: Class 4 Which process that happens in a tree is shown in this picture? Carbondioxide Oxygen C. 2.3% D. 2% B. 52% 3593 Students start learning about basic life processes from class 3. This question was designed to test if students identify the process of photosynthesis correctly based on some details of the process being shown graphically. bout 43% of students answered the question correctly. But 52% of students selected a common wrong answer, B- breathing. Possible reason for choosing B: Students selecting this option are most probably just seeing that carbon dioxide is entering the plant while oxygen is leaving it. Since they know about a similar process of gas exchange i.e. breathing in animals, they choose this option.. Possible reason for choosing C and D: Students selecting these options are most probably guessing randomly. Students observe various things happening around them and in the process of understanding what s going on, they make various kinds of theories based on these observations. These theories may not be scientifically correct. These incorrect notions/ideas are known as alternate conceptions. nd hence it becomes very important for us to know what all alternate conceptions they have regarding a topic and the causes of the same. To handle the problem seen in this question - Understand why students are choosing a particular wrong option. s per our experience students would have different ideas- we have mentioned some common ones above. Before teaching the definition of processes, make sure that students have understood the concept behind the definition. Students should understand the purpose for which a process is occurring they should understand why organisms breathe/respire. If they understand the purpose, they will automatically extend the idea to animals as well as plants. Similarly, they should understand the purpose of photosynthesis. Test students on understanding rather than definitions. For a topic like this, ask them non-standard questions like this that will make them think and also help to assess the level of their understanding. making of food Only 42.6% answered correctly B breathing Students learn about various processes like photosynthesis, respiration etc. But as the data C resting indicates, their understanding is quite superficial. This surfaces if questions to assess their understanding of these processes are asked in a slightly different way. D losing water Students learn about the factors involved in the process of photosynthesis CO 2, H2O, sunlight and chlorophyll, by definition. nd it is this definition that they try to memorize. The given question is testing the same thing they need to see that carbon dioxide gas is being taken in by the plant and oxygen gas is being released. nd since it is occurring in the presence of sunlight, the process is photosynthesis/making of food. Confusion between photosynthesis and breathing: There may be students who think that since water is not mentioned in the figure, the process cannot be making of food. However, they need to realize that if carbon dioxide is being utilized and oxygen is being released, the process cannot be breathing. Students seem to be confused between these two processes respiration and photosynthesis. They learn about respiration, but in context of animals. When it comes to plants, there are some students who think that plants do not breathe/respire. However, there are students who extend the understanding of respiration in animals to that in plants but think that plants do the opposite to that of animals use carbon dioxide and give out oxygen. nd probably they are the ones who are choosing the wrong option B in this question. very good link that shows both the processes occurring simultaneously in plants during the day. n interesting article on students ideas on plant breathing % S

4 Properties of Matter Science: Class 4 Students are familiar with gases and know the basic properties of gases like- air occupies space, air has weight, air is present everywhere etc. This question was designed to test if students appreciate this idea of air being present everywhere, whether it be an open space or a closed one. Who is correct? Teacher : Is there air in the glass? Students : Yes, there is. Teacher : Is there air still in it? Khatija : No, the air came out when it was turned upside down. hmed : No, the teacher's hand absorbed the air Lavanya : Yes, the air is still there. Roopa : Yes, but the quantity of air is less than when the glass is straight. Khatija B hmed C Lavanya D Roopa D. 38.7% % C. 30.3% Only 30.3% answered correctly round 30% of the students selected the correct answer C. lmost 39% students chose the wrong option D and another 20% students selected the wrong option. Possible reason for choosing : These students probably think that just as a liquid falls out when a container is inverted, similarly air will also come out of the container when inverted. Possible reason for choosing B: This appears to be just a random guess. Possible reason for choosing D: These students are probably thinking similarly to those who chose option. They seem to think that only some air will come out as the glass is inverted, and some still remains in it. Possibly, they think that the air comes out of the glass slowly when inverted, and some air remains in the glass, because we keep a hand below the glass before all the air flows out. Students formally learn that air is present everywhere. However, they have been unable to internalize this concept, and their prior ideas about the nature of air, dominate their thinking. s the responses indicate, students seem to be relating air to solids or liquids with which they are more familiar. They have probably seen water or some other solid object like a spoon or a pencil put inside a glass falling out when the glass is inverted, and concluded that a gas would behave similarly.. Some students say that the amount of air that remains inside the inverted glass is less than that in the upright glass. It would be interesting to explore this response further by asking if they think that all the air come out after some time, if the hand is not placed below the glass for a long time.. Students can give up their wrong ideas only when these are challenged by some experience that contradicts their existing ideas. One way to illustrate the fact that air is present everywhere (and even in an inverted glass), would be to use an ink filler. Show it with the rubber bulb down and ask if there is air in it. Now turn it around so that the rubber bulb is up and ask the same question. Students might say that the inverted filler does not have air. Show them that air bubbles come out of the ink filler when it is dipped into a glass of water, and the bulb is pressed. sk them where those bubbles come from and help students to understand that this is because of the air in the ink filler. Students may still feel that the air is present in the water itself. You could help them see that the air is in the filler itself, through another activity. Place a piece of crushed newspaper at the bottom of a cup. Invert the cup and push it down into a tub of water. The paper stays dry because air takes up space and does not let water enter the cup. B. 9.2% Books: Making Sense of Secondary Science Support material for teachers by Rosalind Driver, nn Squires, Peter Rushworth and Valerie Wood- Robinson Routledge Press, London and New York S

5 Habitat, daptation and Ecosystem Science: Class 5 Emperor Penguins in ntarctica are sea birds which dive under water to feed on fish, squids and krill. Which of the following MOST LIKELY helps it to catch its prey in the water without being caught by other predators? Their beaks are short and sharp like those of a sparrow. B They have thick webbed feet which helps them to move fast over land. C Their black and white colours makes it difficult for them to be seen in the sea. D They have plump bodies which do not allow them to dive deep into the waters. C. 28.7% D. 18.6% 6668 B. 18.6% Only 28.7% answered correctly Students learn about the process of adaptation and various examples of plant and animal adaptations. This question was designed to test if students can properly identify the feature that particularly helps penguins to survive in their environment. 29% of students chose the correct option, C; while 33% of students chose the wrong option,. Possible reason for choosing : Students have probably just looked at the term catch its prey in the question stem, and ignored the part that says without getting caught by other predators. Possible reason for choosing B: Students probably think that the webbed feet which help them to move fast could be used to catch the prey, as well as escape from the predators. The fact is that webbed feet hinders fast movement on land and only helps a penguin to swim fast. Possible reason for choosing D: Students are probably making a random guess or think that penguin s predators live deep in the waters and their incapability to dive deeper would help them to survive. For survival in a habitat, an organism has to find food as well as protect itself from predators. For animals, mainly living in their natural habitat, the processes of finding food and protecting themselves go on simultaneously. The survivors are the ones who have a feature that allows them to find their prey without being noticed easily by their prey as well as their predators. The question expects the students to identify one such feature in the case of penguins, which most students have failed to do. They seem to be just looking at certain phrases in the question and trying to get a hint from it to find the answer. They are not looking at the information as a whole and hence ignoring a part of it which is also essential to answer the question. This may be happening because they are not used to such questions which require them to reason in this manner. 1. ctivity: Collect charts of different colours. Divide the class into groups and give one chart to each of these groups. Keep a stack of coloured stones at a distance from the students. Call groups one by one and ask them to place their chart on the ground. Then ask them to place a few stones from the stack on the chart paper. fter this, ask the students who are standing at a distance to identify what colours they can see. Repeat the activity with each group. fter the activity is over, ask the students why students who were standing far not able to see particular colours. 2. llow students to come up with features that can help certain organisms survive in a given environment. Describe the environment, the prey and the predator and ask about the feature. One such example could be it is a herbivorous insect; it lives on dry twigs. What should be the features that will help it escape from its predators? Students will come up with answers like colour, shape, size etc. Facilitate the discussion and allow students to reason out whatever they are saying. Then give the actual example of the stick insect which exhibits such features (See useful resource 1). The idea is to practically demonstrate the phenomenon of camouflage. Elaborate to students how camouflage helps penguins to catch food as well as to protect them from predators. lso keep in mind that camouflage is not the only way of adaptation and other methods of adaptation should also be mentioned, like the enhanced smelling sense in dogs, heat sensors in snakes etc % S

6 Human body Science: Class 5 When we inhale, we breathe in air into the lungs. What do we breathe out when we exhale? B C IR only oxygen gas Inhale only carbon dioxide gas air that has more oxygen than inhaled air? Exhale Only 18.5% answered correctly Students learn about the process of breathing and also that air is a mixture of different gases. This question was designed to test if children are able to reason out that it is air that we breathe in and out of the body, and not just the individual gases. The figure and the question provide a clue, explaining that it is air being breathed into the nostrils. Only about 19% of students answered D correctly. 70% of students believe that only carbon dioxide is breathed out when we exhale! (Option D) Possible reason for choosing : Very few children have chosen this option and this is probably a random guess. Possible reason for choosing B: Children have learnt that we breathe in oxygen and breathe out carbon dioxide, and taken this quite literally. It appears that they do not recognize the distinction between only carbon dioxide and air that has more carbon dioxide. Possible reason for choosing C: Very few children have chosen this option and this is probably a random guess. D air that has more carbon dioxide than inhaled air The body needs oxygen mainly for respiration. It gets this oxygen from the air. lso, since carbon dioxide is one of the by-products of the respiration process, its amount in the exhaled air is more than that in the inhaled air. However it is clearly IR that has to be taken in and not oxygen, since there is no way oxygen alone can be "separated out" before it reaches the lungs. s the data indicates, most children do not seem to be thinking in these terms (i.e. is it carbon dioxide that we exhale, or air that contains more of carbon dioxide?). Some of the possible reasons why children are not able to reason this out- Oxygen being taken in for respiration is taught as a definitional fact. This does not encourage children to be curious about things like- what gas is taken in? Why? Etc. Language used in teaching like we breathe out carbon dioxide is clearly a simplification. Oversimplification like this may lead to misunderstandings and misconceptions. Students may imagine that the nose is filtering out the other gases in the air. Children should be encouraged to reason out things and find answers on their own. Ideally, learnings and definitions should be worked out and summarized by students after the concepts have been internalized through exploration and discussion. In the case of this concept, ask questions like- What is there in air? What gases do we breathe in? Then students may come up with various answers and questions like the nose filters out everything except oxygen what happens to other gases that go inside our lungs? what happens to the oxygen that goes inside and where does the carbon dioxide comes from? The teacher can then use these questions as starting points to go deeper into the subject and help students achieve the necessary understanding. Once students have absorbed the key concepts, they can be helped to internalize this by preparing charts explaining the process and present the same in class. (See the Useful resources section for some good explanations of the process.) Students should be helped to build the confidence to reason out other concepts also on their own. They should learn to see science as something they can learn by asking questions and seeking answers to those questions- not just as facts they need to memorize. Takes us on a tour of the respiratory system. Do click on follow me for the tour nother link which explains the process in simple terms C. 5.3% D. 18.5%. 5.3% 6668 B. 70.3% S

7 Shown here is the picture of an ink filler. When this ink filler is dipped into a beaker of water and the bulb is pressed, air bubbles appear in the water. Why does this happen? C D States of Matter Science: Class 6 ir in the atmosphere forms the bubbles. B The air in the ink filler is released to form bubbles. The liquid rushes into the filler forming bubbles. The air in the water forms bubbles. Ink filler Bulb C. 15% D. 22%. 11% 3000 Only 50% answered correctly The concept of air is introduced to students in class 3. However, even at higher levels, students are not very clear that air exists everywhere, and takes up space. This question was asked to test if students understand that the ink filler also has air in it. Students were expected to answer this question by understanding the facts given in the question (that air bubbles come out), and follow a line of valid reasoning to arrive at the answer. 51% of students have answered B correctly. bout 23% have answered that the air in the water forms bubbles (Option D). Possible reason for choosing : Very few students have chosen this B. 50% option and in all probability this is a random guess. Possible reason for choosing C: By experience, students probably know that the bulb is pressed in order to fill the liquid into the filler. They may have chosen this option seeing the words liquid rushes into the filler. However, they are ignoring the issue of how the bubbles are being formed and are not clear about the exact physical process which causes the ink filler to fill up. Possible reason for choosing D: Students have seen bubbles appearing in water at the mouth of the filler. They probably think that as the bubbles appear in water, they must also come from the water only. It would be interesting to investigate student s reasons for this answer further- perhaps, they have learned about dissolved air in water, or fish breathing in water etc, and have been influenced by these facts. Students were supposed to answer this question based on prior knowledge that air is everywhere and occupies space, and following this up, by applying this knowledge in the given context. However, knowing that the ink filler HS air in it is primarily important. The air coming out of water is the same air that existed in the filler before pressing the filler. When the filler is pressed, the volume of the filler + bulb decreases, which results in the expulsion of some air out of the filler. This air forms bubbles in the water. When the bulb is released, the volume increases and to fill this extra volume some liquid gets into the filler. The student response data indicates that nearly 50% of students are not clear about this- they do not demonstrate an understanding of the property that air occupies space, or a basic understanding of volume/ space and pressure/ flow. This may be the result of learning facts by rote, and not doing simple experiments, and being forced to explain results. Key point of concern Understanding that air exists in the ink filler bility to apply knowledge to explain observed phenomena How to address this? Take an empty ink filler and dip it into water. Keeping the filler inside the water, remove its bulb. Bubbles will rise from the water, when this is done. sk students where these bubbles have come from, and let them appreciate the answer through a discussion. sk students to explain step-by-step, what all is happening when ink is getting filled in the ink filler. What happens when the bulb is pressed? etc, as described in the Learnings section. Similarly do the following experiment and ask students to come up with same step-by-step reasoning. Take a plastic tumbler and a crumpled paper. Place the crumpled paper at the bottom of the tumbler. Invert the tumbler and push it down to the bottom of a tub of water. Take the tumbler out and show the dry crumpled paper. fter this make a hole on the top of the plastic tumbler and repeat the experiment. Show them the wet paper. S

8 Which of these are living things? C D Classification of Living Organisms Science: Class 6 Mango Seed Rice Husk Grass nt Worm ll B Mango seed, grass, ant and worm Mango seed, rice husk and grass Grass, ant and worm D. 57.1%. 12.6% 2683 Only 28.8% answered correctly Students learn about the difference between living and non-living things. The question was designed to test if students can identify the living things from the given group. round 29% of students selected the correct answer B. lmost 57% of students chose the wrong option D. Possible reason for choosing : Students selecting this option probably do not know what rice husk means and think that it is similar to rice which is living. Possible reason for choosing C: Students selecting this option are most probably making a random guess. Possible reason for choosing D: Students selecting this option might have a wrong notion that seeds are non-living. nd since they might be considering rice husk as the same as rice, which is a seed, they are going for this wrong option where both rice husk and mango seed are not mentioned as living. The concept of life is one of the most important ones in biology. Students learn about the characteristic of living organisms and classify objects as living and non-living. But as the data indicates, they seem to have certain notions about living and non-living things which are influencing their responses to this question. Students seem to be unaware of the idea of dormant life. There are many seeds which do not produce a seedling immediately. Instead they live a dormant life and grow into an individual, once the favourable conditions arise. nd since a seed can grow into an individual, it is a living thing. But it seems that students aren t aware of this idea. It could be because they might be attributing the label of living organisms only to things that exhibit explicit characteristics of living things. Since seeds remains inactive for a period of time and do not show any kind of growth like other plants show students might think that it cannot be called living. Students should understand the deeper difference between living and non-living things. llow them to come up with characteristics that make a thing living. For example, show different objects a ball, an egg, a small shrub, an animal, a seed etc and ask them to write down whether it is living or not, along with the characteristics that make them living/non-living. Expose students to various things that do not look as if they are living but actually are living. For example seeds, eggs etc. Take a few seeds and show some of them growing immediately when given the required conditions; whereas keep others inside a fridge or some other place and show that they will not grow unless provided those conditions. Let them understand this idea of dormant life. B. 28.8% C. 1.3% good paper that talks about students ideas about life. good lesson plan on Living vs. Non-living. S

9 C D Reproduction B Metamorphosis Food Chain daptation Living Organisms - Form & Function Science: Class 7 The figure shown here represents which of the following processes? Reproduction Process by which living organisms produce young ones takes place in all living beings. The primary purpose is to procreate their own species for the survival of the species (takes place in). good resource that explains insect metamorphosis. Only 49% answered correctly Students learn about various important processes and definitions. However it is equally important that they understand what those definitions mean and stand for. This question was asked to check if children can identify the process (shown in the diagram) in the development of a butterfly, and whether they can name it correctly. 49% of students selected the correct option B. But 27% of students selected the wrong option (reproduction). Possible reason for choosing : Students choosing this option are probably confused between the terms reproduction and metamorphosis. They do not seem to understand that the process shown here is the process of abrupt growth that metamorphosis is, and not the process of giving birth to young ones. Possible reason for choosing C: Few students have chosen this option and are probably making a random guess. Possible reason for choosing D: Students selecting this option probably think the butterfly takes the latter form to protect itself. For some students, it may just be a random guess. It seems that students have a superficial understanding of terminology. The basic difference between the two processes - reproduction leading to the production of an organism from another organism and metamorphosis leading to the final form of an organism once it is born, is unclear. This is probably because they have learnt the definition without understanding the purpose of the two processes. Following are the key characteristics of the two processes, reproduction and growth, in contrast to each other. It is important for students to understand the difference between different stages in the life cycle of an organism. One of the ways which would help them retain what they learn would be a practical exposure to such processes. Take students on a trip or bring an egg of a butterfly and that of a bird and let them observe the life stages. Though in both the cases it is eggs which on hatching will give rise to individuals, they will observe a clear difference. The bird will be born as a bird and it will just normally grow into an adult. Whereas in case of butterfly, they will see that as time progresses, the larva that had initially hatched from the egg develops into a pupa which finally develops into an adult butterfly. There will be a clear difference in structure and the feeding habit at each different stage. This difference once clear, the processes can be defined as normal growth and metamorphosis. Later on when the butterfly or the bird gives an egg that again hatches into another butterfly or a bird, the process can be defined as reproduction. This kind of exposure where they get to see the purpose of each process will perhaps make much more sense to them than a definition that they have to memorise. C. 10% D. 13% 930 B. 49%. 27% Normal Growth Process of growing of young ones into adults through a gradual change in the size of the body. The primary purpose is to be able to survive independently and become ready to reproduce. Growth Metamorphosis Process of abrupt change in growth - passing through different stages namely larva, pupa and adult organism (in case of butterfly). The primary purpose is to be able to survive independently and eventually become ready to reproduce. Food habits and habitat of larva and adult fly are completely different. This helps in survival because of greater availability of resources. very good resource describing the stages of butterfly metamorphosis. S

10 States of Matter Science: Class 7 When solid candle wax is heated, it becomes liquid. The molecules absorb heat and move apart. B absorb heat and come together. C D release heat and move apart. release heat and come together. C. 25.1% B. 7.2% D. 6.1% 6673 Only 61.1% answered correctly Students have been introduced to the molecular model of matter by this stage, and also know about concepts like melting point and boiling point. This question tests whether children understand how heat can change the state of matter by moving the molecules apart. Interestingly, over 86% of students (those answering and C), do understand that the molecules move apart as wax melts into its liquid form. However 25% of these students believe they do so by releasing heat! Possible reason for choosing B: Very few students have chosen this option and it appears to be a random guess. Possible reason for choosing C: It is difficult to say why children may have chosen this option. Possibly they know from experience that molten wax is hot and may be equating that to releasing heat. They could also be thinking that a candle flame is hot and thus reaching this conclusion. These students do understand that the molecules move apart in the liquid state. Possible reason for choosing D: Very few students have chosen this option and it appears to be a random guess. t least 25% of children do not seem to have a clear understanding of the role that heat plays in melting, and state change. It is given that when wax is heated, it changes to a liquid state. Students know that the molecules in a liquid state are further away as compared to in a solid state. Thus, they should understand that heat is responsible for moving the molecules apart- but this understanding seems to be unclear. Students probably do not appreciate that heat is a form of energy, and how it is related to the energy of molecules. Though these are fairly advanced concepts, it is possible and desirable that there is some intuitive understanding of these concepts by this level. The fact that 61% of students have answered correctly indicates that this is a reasonable expectation. nother challenge children probably face is that they are not used to thinking in terms of the particle model to explain macroscopically observed behaviour % The focus should be to help students grasp the following concepts- 1. the particle model of matter and how it can be used to explain changes we see. (if this is already clear, it is not necessary to spend much time on this) 2. that heat is a form of energy and how this energy is related to the movement/ spacing of molecules in matter The above can be taught in the following manner- List out different states of matter and processes like solid, liquid, melting, evaporation etc. sk groups of students to demonstrate the movement of molecules in these states by moving around, or by drawing pictures of these on the board. Once there is clarity on the movements in each state/ process, ask what heat is and how it is related to these movements. Have a discussion on this, clarify doubts and summarize the learnings and definitions. It is important that students understand that heat is energy, and a kind of movement. More detailed teaching tips and lesson plans are included under Useful resources. Provides and experimental activity, and how children can use the particle model to explain the results. Pages 2 and 3 give some tips on relating heat to movement of molecules. S

11 Living Organisms - Form & Function Science: Class 8 BIOLOGICL CONTROL is a term used to describe the use of living organisms, such as predators, parasitoids, and pathogens, to control pest insects, weeds or diseases. n example of biological control is using a cat to kill mice at home. B pesticides to kill insects. C D medicine to poison food of the pest. scarecrows to scare away birds. C. 11.1% D. 9.8% B. 43.4% 4216 Only 35.1% answered correctly Students learn various definitions and are even able to present these when asked. However they may not be clear about what the definition conveys or the purpose of the process defined by it. This question tries to test if students understand the meaning of a given definition and based on that, are able to identify a relevant example. round 35% of students selected the correct answer. lmost 43% of students chose the wrong option B. Possible reason for choosing B: Students are probably just catching certain words from the definition like control pests and ignoring the part about the use of living organisms. Possible reason for choosing C: These students also have probably latched on to words like control pests in the definition. But since they may not know the term pesticides, they may be choosing this option which says that it s a medicine to poison the food of the pests. Possible reason for choosing D: Students probably think that biological control is about controlling pests and not killing them, and so might be choosing this option since it is the only option that fits this criterion. Definitions are a way of summarizing events/processes in a generalized way. They are not more important than the processes that they are summarizing. However, since students are used to learning and repeating the definitions in a rote manner, they often fail to understand the meaning or purpose behind the definition. They are facing a similar problem in this question. They have already been given a definition which they need to understand and find a relevant example of. But it seems that students are focusing only on certain key words like controlling pests in the definition and missing out other important parts in it like use of living organisms. They are not realizing that control (which in this context means killing), of the pests/insects/weeds has to be achieved using another living organism. sk students to break down definitions into smaller parts. Each part can be considered as a criterion which if satisfied, can lead to the final process that it defines. For example, for this question, the various parts can be Control of unnecessary living organisms like weeds/pests/insects Control has to be killing Control has to be through other living organisms If the above criteria are met, the control can be called a biological control. They can then take an example to check if the criteria are met. For example, option B, use of pesticides to kill pests it satisfies the first two criteria but since pesticides are chemicals and not living organisms, it fails the third criterion and so it is not a biological control. Similarly option D it does not satisfy the second condition and so it fails to be classified as a biological control. You could also ask students to define related terms like chemical control on their own now, to assess whether they have really internalized the other definition. Try such exercises with other definitions that they learn for example, photosynthesis, force etc % good resource that talks about how to teach science in schools. S

12 Living Organisms - Form & Function Science: Class 8 ir contains about 21% oxygen. When we breathe in air, some of the oxygen is used and carbon dioxide is produced. What happens to the NITROGEN in the air we breathe in? It gets converted to proteins. B It is also converted into CO 2. C It comes out of the body unchanged. D Only the O 2 in the air is breathed in and CO 2 is breathed out. D. 32.4% 3025 C. 29%. 28.7% Only 29% answered correctly Students start learning about breathing from class 3. By class 7 they learn about the composition of air and the amounts of different gases in it. This question was designed to test if students understand the fact that it is only the amount of oxygen and carbon dioxide that differs in the inhaled and exhaled air. The other gases remain unchanged in this process. 29% of the students selected the correct answer D. However, around 33% of the students selected the wrong option D and 29% selected the wrong option. Possible reason for choosing : Students probably think that since proteins are rich in nitrogen, this nitrogen might be coming from the air that we breathe in. Possible reason for choosing B: Students selecting this option are most probably making a random guess. Possible reason for choosing D: Students probably think that only O 2 in the air is breathed in and CO 2 is breathed out. They don t think that it is air that is breathed in and out and hence they aren t concerned about the nitrogen in it. The question expects students to have understood the process of respiration. They should have understood that the air that is breathed in is filtered by the lungs, and the oxygen in it is utilised by the body. The lungs also release the carbon dioxide that is brought to it from the entire body by the blood. Hence in the lungs, it is the exchange of only these two gases that happens. However, the inhaled air has other gases, which remain unchanged in this process. Oversimplification of language: cause of misconception: s the data indicates, most of the students are probably unclear about this process and think that it is only oxygen that is breathed in and carbon dioxide that is breathed out. This is an incorrect oversimplification used in lower classes and in science textbooks, which has stayed in the minds of students. Inadequate understanding of digestion and respiration: Some of the students seem to be unclear about the overall process of digestion and respiration. They might have studied that proteins contain nitrogen. But they do not understand that the protein in the body is made from its building blocks provided by the process of digestion. It is not made from the atoms but is made from certain molecules (amino acids). But not having understood this, they tend to think that nitrogen in the air is used by the body to make proteins. Be careful while simplifying language in lower classes. For this concept, instead of saying we breathe in oxygen and breathe out carbon dioxide, use statements like we use oxygen and release carbon dioxide. However, this should also be supported by conveying that air enters the body and from that the oxygen is used. sk questions like 1) Which organ helps in filtering the oxygen present in the air? 2) Will only oxygen enter the nose or will the air enter it? 3) If air, then what will happen to the other gases present in it? These questions can then be taken ahead depending on the responses given by them. B. 9% resource that explains the gas exchange taking place in the lungs. S

13 Living Organisms - Form & Function Science: Class 9 What happens to the individual molecules in a vegetable when we eat the vegetable? B C Individual molecules are always broken down into their constituent atoms during the digestion process. Individual molecules are always completely destroyed during the process of eating and digestion. Individual molecules are always unaffected and stay in their original form in our bodies. D Individual molecules may stay unaffected or their atoms may recombine to form different molecules. D. 25.9% C. 7.3% B. 9.8% 1528 Only 25.9% answered correctly Students learn about the digestive system, its various organs and their roles. They also learn about the digestion process, and what happens to the nutrients in the food during digestion. This question was designed to test if students understand this process and are able to reason out what happens to the individual molecules during the process of digestion. 26% of the students selected the correct answer D. However, more than 50% of the students selected the wrong option. Possible reason for choosing : Students probably think that digestion means breaking down and so the individual molecules will be broken down completely into their building blocks atoms. Possible reason for choosing B: Students are most probably making a random guess. There might be some students who think that the purpose of digestion is to provide energy which is obtained only on complete destruction of molecules. Possible reason for choosing C: Students selecting this option are most probably making a random guess. Students learn about the digestive system and the process of digestion. For this question, they are expected to understand that when food is digested, the complex material is broken down into its constituent simpler parts. So for example, when rice or pulses are eaten, the purpose of digestion is to break down the complex carbohydrates present in them into simpler molecules like glucose, or to break down the proteins to its constituent amino acid molecules. These molecules are then absorbed in the intestine and transported to other organs. The purpose of digestion is to provide these simpler molecules which can then be used by other organs of the body to release energy, or for the maintenance of its cells. But as the data indicates, students don t seem to have internalized this concept. They think that the molecules are broken down into their constituent atoms during the process of digestion. It could be because they tend to learn the process using certain key words in this case digestion as breaking down. They might even be confused between certain terms like atoms, molecules and their alternate usages in chemistry and biology. nd therefore when it comes to a question like this, they are not able to understand the meaning of molecules in this context, as complex molecules and simple molecules. Not being clear about molecules in food and the digestive process probably makes them think that molecules when broken down will give constituent atoms. Let students internalize the concept before exposing them to definitions. For this particular question, let them understand the primary role of digestion first. Having done that, it shouldn t be difficult for them to use different terminologies in different contexts. The process of digestion can be taught by a simple demonstration. Take a necklace made of beads. Each bead is made up of atoms and molecules, but for the necklace, the beads are similar. Draw an analogy between the necklace and proteins. Show how the individual beads get separated during the process of digestion, are absorbed and transported to the cells of the body where they are again used to form a new protein molecule. This should convey that proteins are not made de novo from the atoms but are made from its constituent building blocks % good resource that describes the digestion process. Check the animation on what happens to the food that is eaten at different times. good resource that mentions clear learning objectives and activities for this topic. S

14 Living Organisms - Form & Function Science: Class 9 digital clock uses 4 LEDs similar to the one shown here to display the time. However ONE OR MORE of the segments of the rightmost LED is/are damaged and NEVER light(s) up. Only 33.8% answered correctly Students observe various things in their day-to-day life and they come across many situations where they need to analyse the information available to them and think logically. Here is one such question. The question is about LEDs which they see at various places - watches, elevators etc. The problem demonstrated is also a very common one. Students are expected to answer the question logically using the information given. 34% of the students selected the correct answer C. lmost an equal number of students selected the wrong option. Possible reason for choosing : Students may have understood the question, but are not able to identify the pattern of the missing segment and its implication. Possible reason for choosing B: Students selecting this option haven t understood the question and are probably making a random guess. Possible reason for choosing D: Students selecting this option haven t understood the question and are probably making a random guess. Students need analyse the information given in the question time shown by the defective LEDs. They should be able to infer based on this that the rightmost LED is defective. nd the segment which is not lighting up should be the one shown by arrow in the figure above, because only that is not working and is common in both of them. Based on this they should be able to say that for the time asked in the question, it will be 3:56 and so one minute later, the clock should show 3:57 (since the defective segment is not involved in showing 3:57, it will be seen normally). But as the data indicates, students haven t understood this and are probably just taking the time shown by the clock as the correct time. By this age level, students should be able to analyse this kind of data. They do see many such problems in their day-to-day life. But it appears that most students lack the approach to solve such problems. Ravi noticed these two times on the clock: Right now the clock is showing: One minute later, the clock could show: 4:09 B C 88:88 3:55 3:56 3:58 3:57 3:53 D Students need training and practice in problem solving. The teacher s goal should not to be to show students the answer to a specific problem, but to teach them how to go about solving problems and how to think while solving problems. Some ways to get students to reflect on their thinking processes when solving a problem are: Have students read the problem aloud and explain what is needed to solve it before they start to work. Get students to work problems while thinking out loud. Encourage students to constantly talk about what they are doing and why. Comments or questions like these can help students clarify their thinking: Tell me what you know about the problem. How can you break the problem into small steps? How did you go from step one to step two? Sometimes the teacher may need to demonstrate good problem solving techniques. She may have to demonstrate how to go about reading and understanding a question before starting to work the problem. She may show how to solve the problem, making the process clear to the student. The links under Useful resources provide more details. Explains how to teach problem solving and types of errors made in problem solving C. 33.8% D. 13.4% 1528 B. 15%. 36.3% good resource talking about critical thinking and problem solving skill in maths and science. S :09