CONCEPTS PROCEDURES ATTITUDES. Understanding simple scientific texts Observing and interpreting a sequence of photographs Filling in word maps

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1 UNIT Bones and Muscles PRESENTATION In this unit we will be studying the skeleton and muscles in the human body. We will build on the knowledge the students already have of the human body. This will help them understand the workings of the skeleton and muscles, and how the two are related. In this unit, learners also learn how to observe photographs and illustrations. These skills help them to identify the body s main bones and muscles. UNIT CONTENT Objectives To learn about bones and to understand their main characteristics. To identify some of the bones in the human body. To learn about muscles and understand the different types. To understand that muscles and bones must work together in order to produce movement. To read and understand simple scientific texts. Contents CONCEPTS PROCEDURES ATTITUDES Bones and their functions Cartilage and joints The skeleton Muscles and their functions Bones, muscles and movement Understanding simple scientific texts Observing and interpreting a sequence of photographs Filling in word maps Respecting and caring for physically handicapped people Assessment criteria Understanding that the skeleton is made up of bones, cartilage and joints Understanding what joints are, what they are used for, and distinguishing between fixed and moveable joints Identifying certain bones in our own bodies Understanding what muscles are, recognizing some of the most important muscles, and understanding the difference between voluntary and involuntary muscles Explaining how bones and muscles work together to produce movement Understanding and recognizing the difficulties faced by people who are physically handicapped T18 A

2 UNIT 0 RESOURCES Resource Book Reinforcement and extension Reinforcement: Worksheets 3 and 4 Extension: Worksheet Test and assessment Assessment: Worksheet Internet resources Muscles _interactivebody.shtml The muscles game The skeleton swf Information about the human skeleton Bones and jqoints Learn about bones T18 B

3 Bones and Muscles Anticipating Difficulties Keep the following things in mind while doing this unit: Some students may not realize that bones are living parts of the body. They may think they are inert. Explain that bones can break, but that they can heal themselves, too. This is fundamental proof that they are living matter. Students often find it difficult to distinguish between a voluntary and an involuntary muscle. Pulling our hand away when we prick it or burn it is a reflex action, not an involuntary one. It is done by voluntary muscles, in this case, the biceps. One example of involuntary movement is when the hair on our skin stands up if we are cold or frightened. The muscles in the stomach and the intestines also make involuntary movements when we are digesting food. Teaching Suggestions When your students read the text, ask the following questions: Why are archeological remains always bones and teeth, and not muscles or other organs? Why do we find remains of large animals like men or bears and not small birds or insects? Why are these archeological finds so important for scientists? Review the diagram of the human body, and ask your students to name the parts of the body. Ask where the parts are: in the head, the trunk or the limbs. Then ask them to name only those parts of the body that can bend, like fingers or arms. Ancient Bones The other day I saw a show about an archaeological site. One of the scientists said that bones talk to us. What do you think this means? Archaeologists have found lots of bones on the site. The bones are more than 300,000 years old. There are teeth and a lot of small pieces of bone. I know bones are hard, but I didn t know that bones could be so old. It is almost impossible to destroy bones. When scientists look at bones, they work like detectives. They put the skeletons together like a jigsaw puzzle. Then they use the bones to find out about ancient man. A small piece of bone can tell them a lot. It can tell them how old a person was, if the person was healthy or sick, and what food they ate. This is why scientists say that bones talk to them. Isn t it incredible that such a small piece of bone can give us such a lot of information? Julie, age 9 18 ALTERNATIVE SUGGESTIONS Another way to demonstrate the importance of both bones and muscles is to play a simple game. Fill a balloon with water, and try to hold the balloon using only two or three small sticks or pieces of wire. Students will see how difficult it is to do this. Explain that this is what would happen if we had bones but no muscles in our body. Bones aren t much use without muscles. T18

4 1 Talk about the text UNIT Answer the questions. What did the archaeologists find at the site? How old are the bones? What can we find out from a piece of bone? Play with a friend. Point to parts of your body. Name the different bones. Think about the questions Answer the questions. Read the texts. What is under the skin? If we cut the skin, we can see flesh. This is made up of muscles. If we cut even deeper, we can see bones. Could we walk if we didn t have muscles in our legs? What would happen if we didn t have any bones? We need muscles and bones to walk and move around. Bones and muscles have to work together for us to move. Check what your students already know about bones and muscles by asking questions. Tell them to look at their arm or leg and ask: Is it hard or soft? Is it rigid or does it lose its shape? Does it look the same when it is resting as when it is moving? Is it one single piece or is it made up of more than one piece? Can you name the pieces? Citizenship Environmental education Picking flowers and plants or collecting rocks and fossils destroys our natural environment. In many places it is also forbidden. Ask the students to think what would happen if everyone took home a fossil, a rock or a plant every time they went out or visited an archeological site. 3 Find out about the unit In this unit we are going to learn about: Our skeleton and our bones. Our muscles and how they work. 19 Ask the students to stand in a circle holding hands. Ask one student to name parts of the body that bend (neck, shoulder, elbow, wrist, fingers, hips, knees, ankles, toes). Continue with others in a chain. When all the joints have been named, continue with parts of the body in the head, trunk and limbs. Talk about the text The archaeologists found a lot of bones at the site. The bones are more than 300,000 years old. A piece of bone can tell us how old the person was, if the person was healthy or sick and what food they ate. Model answer: skull, ribs, femur, tibia, etc. T19

5 Bones and the Skeleton 1. Bones Bones are the hard, rigid parts of our body. Our bones hold our body up. They protect delicate organs like our brain and heart. They also help us move around. Bones have different shapes: 1 Some bones are long, like the femur. The femur is the longest bone in the body and is found in the leg. Some bones are short, like a vertebra. A vertebra is found in the spine. Others are flat, like the skull bones in our head. Flat bone: temporal OBJECTIVES To understand what bones are like and what their function is. To understand that the skeleton is made up of cartilage and bones. To understand that joints are absolutely necessary and to identify the different types. Long bone: femur Short bone: vertebra Teaching Suggestions. Cartilage Cartilage is a flexible part of the skeleton. It is not as hard as a bone. We have cartilage in our nose, ears and at the ends of our bones. The skeleton is made up of bones and cartilage. 1 Types of bones. Bones can be long, short or flat. Introduction Ask your students: Where is your knee? Can you bend it? Do you have bones in your head? Do they look like the ones in your leg? Do you have bones in your back? Are they like the ones in your head? Are they big or small? Make a note on the board of the different types of bones and joints: small, big, fixed, moveable. Ask the students to choose a simple movement they perform often like raising an arm, walking up a step, etc. Ask them to imagine how they would do this if they didn t have bones: Could you raise your arm if you didn t have any bones? 3. Ligaments Joints are the places where two bones join together. There are two types of joints: fixed joints and moveable joints. Fixed joints are where the bones do not move, for example, in the skull. Moveable joints are where the bones can move in one direction, for example, the knee. These joints are held together by ligaments. 0 Ligaments In knee joints, bones are joined together by ligaments. Explanation Students may find the concept of a fixed joint rather difficult to understand. If so, give this example of the bones and joints in the skull. In an adult, these joints have no function whatsoever. However in a baby, they do. In a baby, these joints enable the skull to change shape slightly so that the child can be born. Explain that cartilage is lighter and more elastic than bone, but very strong. We have cartilage in our ears, nose and trachea. INTERESTING INFORMATION Cartilage skeletons Sharks are extraordinary animals. One of their most incredible features is that their skeleton is made entirely of cartilage. This means that sharks can swim very fast, and they are extremely agile. The oldest shark fossils that have been found to date are approximately 400 million years old. Sharks have not evolved much over this period of time because their natural habitat, the ocean, has not changed much either. They are excellent swimmers, and they seem to glide through the water propelled along by their powerful tails. T0

6 4. The skeleton There are more than 00 bones in our body. Here are the names of some bones: 3 The head: the skull and the bones in the face, like the upper jaw. The trunk: the vertebrae, which make up the backbone, and the ribs, which make up the chest or thorax. The arms: the humerus, the ulna, the radius and the bones in the hands. The legs: the femur, the tibia, the fibula and the bones in the feet. Vocabulary thorax the bones that surround our heart and lungs Tasks 3 clavicle skull The human skeleton 1. What are bones? Name three different bone shapes.. What are joints? Name two different types of joint. temporal scapula (shoulder blade) sternum (breast bone) 3. Look at picture 3. Name two bones in the head, two in the trunk and two in the limbs. ribs femur knee tibia fibula vertebrae pelvis parietal frontal maxilla (upper jaw bone) mandible (lower jaw bone) humerus (funny bone) ulna radius carpals, metacarpals and phalanges (finger bones) tarsals, metatarsals and phalanges (foot and toe bones) 1 UNIT Understanding After asking the questions in the book, continue with these: Which joints can you point to and name in your body? What actions can you do with these joints? Can you hop/skip/read? Imagine your knees and elbows were fixed joints. Could you jump/hop/run/throw a ball/write? Draw a diagram of the human body on the board. Ask volunteers to come to the board and draw the bones. Help them with the names. They should be able to identify their position and approximate size. Citizenship Health and hygiene A balanced diet is essential for a healthy body. Milk and dairy products are an important part of a healthy diet. Dairy products give our bodies proteins, carbohydrates, and above all, calcium, which is essential for healthy bones. Explain that it is important to drink and eat dairy products while you are growing. Note: If you have students who are allergic to dairy products, explain that calcium is also obtained from other sources like green vegetables. LEARNING SKILLS Reading comprehension Reading comprehension means reading a text and understanding the meaning. Students must read carefully and understand the meaning of most of the key words so that they can get the general meaning of the text. Ask your students to read Ligaments. Write three sentences on the board to summarize the text, and ask students to choose the one that best summarizes the main ideas. For example: This text is about all the parts of the body. This text is about some parts of the body. This text is about fixed and moveable joints. 1. Bones are the hard, rigid parts of our bodies. Bones can be long, short or flat.. Joints are the places where two bones join together. Joints can be fixed (the joints can t move) or moveable (the joints can move). 3. Model answer: Bones in the head: maxilla, parietal; bones in the trunk: sternum, ribs; bones in the limbs: tibia, femur. T1

7 ACTIVITIES UNDERSTAND UNDERSTAND 1. The skeleton. You can extend the activity by using other words from the lesson, for example: cartilage, vertebra or thorax. 1. Use the words to complete the sentences. ligaments joints The skeleton is made up of and cartilage. Bones are joined together by. hold bones together at the joint.. Look and write the letters next to the names of the bones. bones The skeleton is made up of bones and cartilage. Bones are joined together by joints. Ligaments hold bones together at the joint. vertebrae maxilla (upper jaw) A B C carpals (finger bones) Do you and you classmates have X-rays of yourselves? If so, bring them into class. Look at them. What bones can you see?. Identifying bones. Students often know more than they think. For example, they know many of the bones in the body even though they do not know the names. FIGURE IT OUT 3. Answer the questions. Imagine your leg is one long bone. Could you walk? Could you jump or hop? How many joints are there in your index finger? Imagine you have no joints in your fingers. Could you write? A. carpels (finger bones) B. vertebrae C. maxilla (upper jaw) FIGURE IT OUT APPLY 4. Copy the movements in the pictures. Which joints do you use for each movement? Make a list. A B 3. The importance of joints. This activity is designed to stimulate reasoning. In order to answer the questions, students will have to reach their own conclusions using what they have learned in this unit. Model answer: I wouldn t be able to walk, run, jump or do any activity in which I had to lift my legs off the ground. I can t lift my legs without bending them. The index finger has three joints. If I didn t have any joints in my fingers, I wouldn t be able to bend my fingers, pick things up or write. ADDITIONAL ACTIVITIES Bending a bone Bones are made up of calcium and other elements that are also found in rocks and that make them very hard. However, it is possible to make a bone soft and pliable if we eliminate most of these elements. Materials: A chicken or turkey leg bone A glass pitcher Vinegar T

8 LEARNING TO READ UNIT 5. Read the text. Answer the questions. What Bones Are Made of The bones in our body are very hard, and they last for a long time. They contain a lot of calcium and other elements. These elements are also found in rocks. Bones are rigid and do not bend or change shape, but they can break. Our bones are living things. They grow and they need food. Our bones use the food to repair themselves. DIBUJO APPLY 4. Joints and movement. Your students will find it easier to identify the joints if they perform the movements themselves. The boy bends at the hip, and the girl bends her elbow. What are our bones like? Choose the best words. Soft and flexible. Hard and rigid. Red and rough. Why are bones living things? Can we heal a broken bone? How can doctors help the process? Which things in the picture are rigid? LEARNING TO READ 5. What bones are made of. This activity provides new information and applies concepts the students have been working with. Point out that bones grow, and also get older, just like any other organ in our body. Summary Bones and the Skeleton The skeleton consists of bones and cartilage. Bones are the hard parts of our body. Cartilage is softer than bones. Bones are hard and rigid. They are living things because they grow, need food and can even heal themselves. Yes, we can. Doctors put on a plaster cast where the bone is broken. This stops us from moving the bone while it is healing. They take X-rays and see if it is healed before they take the cast off. The hard objects are: the brick, the baseball bat and the screwdriver. Instructions: Take all the meat off the bone so it is nice and clean. Put the bone in the glass jar, and cover it with vinegar. Leave it for a few days. Change the vinegar once in a while so that it does not lose its acidity. Take the bone out of the jar, and show it to the students. They will see that we can now bend the bone as if it were rubber. Explain that the minerals in the bone have dissolved, and without these minerals the bone is pliable. 3 Language link Teach the following rhyme: Imagine how floppy my body would be, If my skeleton was made of jelly. (Flop onto the floor.) My legs would wobble and fall about, (Wobble legs.) I wouldn t be able to stretch them out. (Point to bent legs.) My neck would fall onto my chest, (Drop neck onto chest.) No, I think having bones is probably best! (Stand up straight.) Resource Book F Reinforcement and extension Reinforcement: Worksheet 3 T3

9 Muscles 1. What are muscles like? OBJECTIVES To know what muscles are like, and what they are for. To relate the different types of muscles with the kinds of movements they make. To understand how muscles and bones work together to produce movement. Teaching Suggestions Introduction Before you begin the lesson, do an exercise with your students to clarify the concepts of hard, rigid, elastic and soft. These are important adjectives for describing both bones and muscles. Give your students various objects that they can describe using these words. This will help you make sure they understand the meanings. Explanation When your students have studied the definition of muscles and types of muscles, explain that we have more than 600 different muscles in our bodies. This makes up almost half our body weight. At least 400 of these 600 muscles work together with bones to produce movement. Explain that our muscles are the soft fleshy part of our bodies. In fact, when we eat meat, we are eating animal muscles. Ask your students to sit still without moving for a while. Ask them if they can see any classmates making movements. Explain that even though people are not moving, they still make involuntary movements: breathing, heartbeat, digestion, etc. Muscles are soft and flexible. They enable us to move our body. They also give shape to our body. Some muscles are joined to bones. Others form part of internal organs like the stomach or the heart.. Types of muscles There are voluntary and involuntary muscles. Voluntary muscles are muscles we can move when we want to. 1 For example, when we want to move our arm, we use the biceps muscle. Involuntary muscles move automatically. We do not make them move. For example, the heart muscle moves automatically. 3. Muscles move bones Muscles get longer and shorter. A muscle gets shorter by pulling on the adjoining bones. Bones and muscles work together to move our body. Muscles are joined to bones by tendons. Bones and muscles make up the musculoskeletal system. 4 ADDITIONAL INFORMATION 1 Voluntary muscles in the face. We use the muscles in our face to show feelings. These are voluntary muscles. A tendon The arm bends. B The triceps gets shorter. The arm straightens. The biceps gets shorter. Movement of the arm. In A, the biceps gets shorter and the arm bends. In B, the triceps gets shorter and the arm straightens. Involuntary muscles Students often find the difference between voluntary and involuntary muscles confusing. Explain that most involuntary muscles in the human body are part of internal organs, such as the heart, the intestines, the arteries, etc. These muscles are slower and they contract more slowly. They can, however, make more sustained, constant movements. A typical example is the heart and the heartbeat. T4

10 4. Muscles UNIT Every part of our body has muscles. Here are the names of some of them: 3 The masseters are in the face. They move the chin and other parts of the face. We use them to make facial expressions. There are lots of muscles in the trunk, for example, the pectoral, abdominal and dorsal muscles. The biceps and triceps are in the arms. The quadriceps and the gemellus are very strong muscles. They are found in the legs. Tasks 1. What is a muscle? Name five muscles. 3 abdominal sartorius quadriceps Muscles in the human body. Is the heart muscle different from the biceps? How is it different? 3. Look at picture. Explain how you move your arm. masseter deltoid pectoral biceps gluteal gastrocnemius rotating muscles (gemellus) trapezius dorsal triceps biceps femoris refractor muscle Understanding Ask your students to bring in pictures showing people making some kind of movement or doing exercise. They can use newspapers or magazines. Sports magazines are especially good. This activity shows the students different kinds of movement and makes them think about how they are made. They can point out the muscles and bones involved in each movement. Use the pictures to ask your students if they can see any difference between their own muscles and the muscles of the athletes. What do you think the reasons are for these differences? What happens to our muscles if we do a lot of exercise? Citizenship Health and hygiene We should do a lot of exercise to keep our muscles healthy and stop them from losing strength and elasticity. Walking, running or swimming are healthy, complete exercises because they help us to develop and maintain all the muscles in our body. LEARNING SKILLS Words in bold Relevant information in a text is usually printed in bold to make it stand out. Bold is used for definitions, concepts, key words, etc. Ask the students to read the words in bold in the text on Muscles, page 5. Then ask: Which words are in bold in each paragraph? What is the text about? Which paragraph gives us information on the muscles in the trunk? 5 1. A muscle is a soft, elastic organ that is responsible for body movements. Model answer: masseter, gemellus, sartorius, gluteal, triceps.. The heart is made up of involuntary muscles. The biceps is a voluntary muscle. 3. Model answer: The biceps gets shorter, pulls on the bone it is joined to, and pulls your arm up. When you stretch out your arm, the triceps gets shorter, and pulls the arm down. T5

11 ACTIVITIES UNDERSTAND 1. Circle the correct words. Copy the text. UNDERSTAND 1. Muscles and bones. This activity helps your students memorize main concepts of bones and muscles. The human skeleton consists of bones. Tendons join the muscles to the bones. A muscle gets smaller when the adjoining bone is pulled. The human skeleton consists of muscles / bones. Ligaments / tendons join the muscles to the bones. A muscle gets shorter / longer when the adjoining bone is pulled.. What is the difference between voluntary and involuntary muscles? Classify the following muscles. tongue heart quadriceps abdominals voluntary involuntary. Voluntary and involuntary muscles. Students will understand these concepts better if they have to discriminate between voluntary and involuntary muscles. Voluntary muscles move when we want them to, but involuntary muscles move without us having to do anything. Voluntary: the tongue, quadriceps and abdominals. Involuntary: the heart. 3. Match the words to the picture. masseter biceps heart FIGURE IT OUT 4. Answer the questions. pectoral abdominal gemellus 3. Muscles in the body. Extend this activity by varying the names of the muscles, or including bones as well as muscles. Say the names of the bones and muscles out loud, and ask students to say where they are located. 6 What would happen if the heart were a voluntary muscle? What would happen if the abdominal muscles were involuntary? Masseter: head. Biceps: arm. Heart: trunk (in the chest). Pectoral: trunk (in the chest). Abdominal: trunk (stomach). Gemellus: leg. ADDITIONAL ACTIVITIES Make an articulated arm Materials: Two pieces of construction paper cm Washer and hooks Scissors Glue A butterfly clip A piece of string A rubber band B string rubber band A T6

12 I CAN DO IT UNIT 5. Look at the pictures. Read the texts. Pictures can show how you move your body. 1 arm and hand muscles First, the muscles in the hand and arm pull on the bones. This closes the hand and holds the weight. Lifting and putting down a weight biceps Then the biceps gets shorter, and pulls on the radius. The arm bends at the elbow. Look at the pictures. Complete the sentences. radius Moving a leg backward and forward triceps ulna Finally, the triceps gets shorter, and pulls on the ulna. The arm stretches out and puts the weight down. 1 3 quadriceps biceps femoris biceps (hamstrings) femoris 3 FIGURE IT OUT 4. Muscles from the front and back. This activity stimulates logical reasoning and written expression. Model answer: If the heart were a voluntary muscle, we would have to remember to make it beat all the time. Model answer: If the abdominals were involuntary muscles, we wouldn t be able to sit down or stand up. I CAN DO IT 5. Picture sequences. Check that students interpret each sequence correctly. Have them identify which muscles are moving and the effect their movement produces. First, the biceps femoris gets shorter and the leg bends. Summary Then. Finally, Muscles Muscles are soft, flexible organs. Tendons join our muscles to our bones. Some muscles are voluntary. Others are involuntary. Instructions: Tell your students to draw the outline of their hand on a piece of construction paper. Tell them to cut it out, and glue one end to construction paper A. Students join the two pieces of construction paper using the butterfly clip, and place the hooks along the edges as shown in the diagram. Tell them to cut the string and a rubber band about 0 cm long and pass them through the hooks as shown in the diagram. Tie the end of the string to the washer so that when they pull the washer, the arm bends. 7. Then the quadriceps gets shorter and the shin moves forward. Finally the biceps femoris gets shorter and the leg bends. Language link Work with the words students need to describe a sequence of events: First Then After that Finally Ask them to use them to describe simple sequences. For example: How do you brush your teeth? How do you take a bath? Resource Book F Reinforcement and extension Reinforcement: Worksheet 4 T7

13 Now I Know Check what you know 1. Complete the word map. Unit Review Before you do the activities in the Student s Book, remind the students of the main ideas presented in the unit. You can dictate sentences, for example: The skeleton is made up of all the bones and cartilage. Bones are the hard, rigid parts of the body. Bones hold our body up, protect our internal organs and help us to move. Cartilage is the softer, more flexible part of our skeleton. Joints are the places where our bones join together. They can be fixed or moveable. Muscles are soft, elastic organs. They are responsible for movement. Muscles can be voluntary or involuntary. Physical education link Tell your students to perform the following actions and think carefully about the parts of their bodies that they move in each case: Jump Write Run Hop Then ask them to say which actions require moving the largest number of bones and muscles.. Mark the correct words. 8 are hard and rigid 1 1. What kind of organs are bones? Hard. Flexible.. The is made up of bones. muscles skeleton 3. What kind of organ is cartilage? Hard. Flexible. 4. Muscles are in the arm. The musculoskeletal system joined together by can be made up of moveable all over the body. 5. Tendons join muscles to other muscles. the bones. are muscles Copy and complete the sentences. Use words from the word map. are soft and 4 voluntary 5 The musculoskeletal system is made up of bones and. Bones are hard and. are places where bones are joined. They can be. Muscles are. 3 ADDITIONAL ACTIVITIES 6. When a muscle gets shorter, it pulls pushes on a bone. on a bone. 7. What kind of joint is the knee? Fixed. Moveable. 8. The musculoskeletal system consists of bones and muscles joints. and bones. Muscles get tired Explain that our muscles get tired when we do the same movement several times in a row. We can check this by doing the following experiment. Materials: A clothespin A hardcover book that can be held in one hand T8

14 My project UNIT 3. Make a model of a backbone. A backbone consists of vertebrae that are joined together. Make a model using paper and rubber bands. Now I Know 1. ➀ bones; ➁ joints; ➂ fixed; ➃ elastic; ➄ involuntary. The musculoskeletal system is made up of bones and muscles. 1. Cut a sheet of paper in strips cm wide. Use tape to join two strips together. This should give you four long strips.. Roll each strip of paper around a pencil. Use tape to join the ends together. You now have a thin tube. Remove the pencil. Make more tubes with the rest of the paper. 3. Pass a rubber band through each tube. Put an open paper clip on each end of the rubber band. This will keep the rubber band in place. What does each small tube represent? What does the line of tubes represent? Citizenship 4. Read the text. Do the activity. Moving around People move around all the time. In this unit you studied the body and how you move using your skeleton and muscles. Many people can t move around easily. They need a wheelchair. Imagine how difficult it is to be in a wheelchair. Draw the route you take from the school entrance to your classroom. Now, imagine you have to follow this route in a wheelchair. Mark all the obstacles you find on your route. Bones are hard and rigid. Joints are places where bones are joined. They can be fixed or moveable. Muscles are soft and elastic.. 1. Bones are hard.. The skeleton is made up of bones. 3. Cartilage is flexible. 4. Muscles are all over the body. 5. Tendons join muscles to the bones. 6. When a muscle gets shorter, it pulls on a bone. 7. The knee is a moveable joint. 8. The musculoskeletal system consists of muscles and bones. My project 3. Each tube represents a vertebra. The line of tubes represents the spinal column (backbone). Citizenship 9 4. Model answer: I wouldn t be able to climb the stairs to enter the school. Instructions: Tell your students to hold the clothespin between their thumb and index finger. Then ask them to count the number of times they can open and close the pin in 30 seconds. Then tell them to do the action two more times, and write down how many times they opened and closed the pin in 30 seconds. They will see that they get slower and slower. Now tell them to hold the book down at their side and to lift their arms out until the book is level with their shoulders. Tell them to lower their arm again. They do this for 30 seconds and write down how many times they raised and lowered their arm. Tell them to do this two more times and count. They will see that they get slower and slower as their arm gets tired. Resource Book F Reinforcement and extension Extension: Worksheet F Test and assessment Assessment: Worksheet T9