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Baltimore Curriculum Project Draft Lessons

Introductory Notes

These lessons generally follow the grade-by-grade topics in the Core Knowledge Sequence, but they have been developed independent of the Core Knowledge Foundation. While the Core Knowledge Foundation encourages the development and sharing of lessons based on the Core Knowledge Sequence, it does not endorse any one set of lesson plans as the best or only way that the knowledge in the Sequence should be taught.

You may feel free to download and distribute these lessons, but please note that they are currently in DRAFT form. At this time the draft lessons on this web site do NOT have accompanying graphics, such as maps or cut-out patterns. Graphics will be added to this site later.

In participating BCP schools, these lessons are used in conjunction with the Direct Instruction skills programs in reading, language, and math. If you use or adapt these lessons, keep in mind that they are meant to address content and the application of skills. You will need to use other materials to ensure that children master skills in reading, language, and math.

Second Grade - Science - Lesson 15 - Simple Tools and Machines

Background Information for Tools and Simple Machines Unit

Tools and simple machines are used to help you do a job more easily, with less effort and difficulty. Machines can chop wood, lift or move heavy objects, make holes, etc. Before the machine age work was much slower and more backbreaking. Imagine trying to dig a large hole with your bare hands, instead of using a shovel. Imagine having to climb a pole to put up a flag, instead of using a rope and pulley. By using a machine, less effort and energy is needed to complete tasks in our everyday life.

When you think of a machine, what comes to mind? Do you think of washing machines, lawn mowers, computers, power tools? Sometimes these types of machines are large, noisy, and complicated, but nevertheless, they make it easier to complete a job. These machines are known as complex machines. Complex machines are made up of different kinds of simple machines. Simple machines do not contain many parts.

Tools and simple machines have been used for many centuries to make work easier. It is generally agreed that there are six simple machines: the lever, the pulley, the screw, the wedge, the inclined plane, the wheel and axle.

All machines are used to make a job less difficult. They do so by allowing a small effort or force to be used to raise or move a heavier weight or to exert a greater force.

Objectives

Examine and become familiar with nails and screws.

Name hardware and tools and the jobs they do.

Materials

Nails, screws, hammer, screwdriver

Plastic containers (Put a mixture of nails and screws in containers.)

Possible guest speakers for this unit

Invite a carpenter or engineer to speak to the class about tools, which tools were needed to make an object (a table, a closet), or have them construct an object in front of the class.

Suggested Books

Beim, Jerrold. Tim and the Tool Chest. New York: Morrow, 1951.

Gibbons, Gail. Tool Book. New York: Holiday House, 1982.

Robbins, Ken. Tools. New York: Four Winds Press, 1983. (This book contains photographs of tools to show the class.)

Rockwell, Anne and Harlow Rockwell. The Toolbox. New York: Macmillan, 1971.

Weisenthal, Ted and Eleanor. Let's Find Out About Tools. New York: Watts, 1969.

Procedure

Tell the children that people use tools to make and fix things. Say: Tools make it easier for us to get a job done. It takes less time and effort if we use a tool to make something or fix an item that is broken. Ask: Can anyone name a tool? Call on different children to name different tools (hammer, screwdriver, wrench, pliers, saw, shovel).

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Second Grade - Science - Lesson 15 - Simple Tools and Machines

Tell the children that throughout history people have used tools to work on a task. The earliest tools were made from wood, stone, or animal bone because these were the materials available, but when iron, which is a metal, was discovered it was used to make tools.

Read the following excerpt from What Your Second Grader Needs to Know to the children:

Imagine digging up a whole garden with a stone or stick, and then think about how much easier it is to use a shovel with an iron blade. The discovery of iron was so important that we call the ancient time of its discovery the Iron Age.(1)

The iron used to make the tools not only made the tools stronger, but the iron could also be melted down and made into the shape that was needed for the tool.

Tell the children that specific tools are made to do specific jobs. A hammer is used to pound nails into wood and a screwdriver is used to turn screws into wood. You wouldn't want to use a hammer with a screw, nor would you want to use a screwdriver with a nail.

Have the children work in teams of four. Ask one member of the group to act as the runner who gets and returns group materials. Have the runner pick up the materials for the group (nails and screws in plastic containers). Have the groups examine the nails and screws and have them report to the class the differences and similarities they notice between the two pieces of hardware. (The nail has a flat head and the screw has a rounded one with indentations in it. The nail has a straight body and the screw has grooves on it. They are both made of metal.)

Show the children a hammer and a screwdriver. Remind the children that a hammer is used to hit something and a screwdriver is used to turn something. Show the children a hammer and have them hold up the piece of hardware that should be used with the hammer. Ask: What are you holding up? (a nail) Can someone tell me a reason why you use a hammer to pound in a nail? (flat head, straight, smooth body) Next show the children a screwdriver and ask them to hold up the appropriate piece of hardware. Ask: What are you holding up? (a screw) Can someone tell me a reason why you use a screwdriver to turn a screw into wood? (slot on the head for the screwdriver to go into, grooved body to grab and turn into material)

NAME ___________________________



Place the name of the tool next to each description.





1) Put the nail into the wood. __________________



2) Cut the wood. ________________



3) Put a screw into the wood. _______________



4) Make a hole into the wood. _______________





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Second Grade - Science - Lesson 16 - Tools and Simple Machines

Objectives

Name a simple machine that acts like a lever.

Observe how a lever works.

Materials

1 wide marker, 1 ruler, pennies (milk jug lids, unifix cubes, etc.) per pair of students

Optional: hammer, bottle opener and closed bottle, sand pail and shovel

Suggested Books

Dunn, Andrew. Lifting by Levers. New York: Thomson Learning, 1993.

Horvatic, Ann. Simple Machines. New York: Dutton, 1989.

Rockwell, Anne and Harlow Rockwell. Machines. New York: Macmillan, 1972.

Weiss, Harvey. Machines and How They Work. New York: Thomas Y. Crowell, 1983.

Procedure

Tell the children that in addition to tools, people also use machines to get a job done. Say: When people usually think of machines they think of big machines that are made of many different parts, such as a washing machine or a car; these are complex machines. The machines we are going to learn about today are small and are called simple machines. Explain to the children that simple machines are machines that have few or no moving parts and help people to make and/or fix things. When using a simple machine you have to put forth effort and energy to get work done, but the machine makes the task easier.

Make sure that the children understand the difference between the two types of machines - simple and complex. Tell them that complex machines are made up of different kinds of simple machines. Name some examples of complex machines (lawn mower, clothes dryer, automobile, vacuum cleaner, etc.) and compare them to simple machines (such as a screw or a wheel and axle). Remind them that both types of machines help you to complete a task more easily and allow you to do things you might otherwise not be able to do.

Say: Today the class will examine a type of simple machine called a lever. A lever helps lift weight with less effort than if you simply tried picking an object up.

 

The simplest kind of lever is just a straight stick or board and something to rest it on. Suppose you want to move something heavy--for example, a big rock in the corner of your garden. You can push one end of a strong board under the edge of the rock. Then you can rest the middle of the board on a log. This will be the resting place, or fulcrum (FUHL kruhm). The end of the board near you will stick up--and the heavy rock will move, too.(2)





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Second Grade - Science - Lesson 16 - Tools and Simple Machines

Draw a diagram of this on the blackboard. Tell the children that if they were to use their own strength to push the end of the board that is sticking up, the rock could be lifted slightly. Draw a

diagram of a seesaw on the blackboard. Tell the children that a seesaw is a kind of lever. Ask: Does anyone see similarities between the first diagram and the seesaw? Discuss the two diagrams with the class.

Have the children get into pairs for this part of the lesson. Ask one person from each pair to act as the runner. Ask the runner to pick up the supplies (pencil, ruler, 2 different coins). As you are walking around the room, give the following directions:

Place the pencil on your desk.

Place the ruler across the pencil.

 

Tell the children that the lever we are putting together acts like a seesaw. A seesaw is a board on a stand, just like our ruler on the pencil. A seesaw acts as a lever when it is used to lift a person off the ground. If you tried to lift your friend with only your arms, it would be difficult. If you use a simple machine called a lever (the seesaw), you will be able to lift your friend much more easily.

Next, tell the children:

Place one penny (milk jug lid, or cube) on one end of the ruler.

Place one nickel (two cubes) on the other end of the ruler.

Ask: Where is the coin that is lighter in weight? (in the air) Why is this happening? (The weight of the heavier coin is pushing down on that end of the lever.)

Discuss with the class other machines that act as levers (the claw of a hammer when pulling out a nail, a bottle opener, a shovel). Bring in items to demonstrate if possible. Ask the children what job each machine does.

Ask all runners to return equipment from the experiment.



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Second Grade - Science - Lesson 17 - Simple Tools and Machines

Objective

Observe how a pulley works.

 

Materials

Broom handle

Rope

Procedure

Ask the children to recall the type of simple machine they learned about in the last lesson (the lever). Tell them that today we will learn about another simple machine called a pulley. The pulley, like the lever, makes a job easier to accomplish. Say: A pulley is made of a rope or wire and a wheel. The wheel is suspended or hanging.

Read the following explanation to the children:

 

The rim of the wheel is grooved so that a rope or steel cable can fit around it. When one end of the rope is pulled down, the rope slides over the wheel, which turns on the axle. Then the load at the other end moves up.

With one pulley, the load moves up as far as you pull the rope down. You work just as hard to pull the rope as you would to pick up the load--but you can pull in a direction that is easier for you.(3)

Ask the children if they have ever seen a flag raised up a flagpole. Have a child explain how the flag was raised. If no one knows, explain that there is a rope attached to the left hand side at the top and the bottom of the flag. The rope passes through a wheel at the top of the pole and hangs down to the ground to form a pulley.

Demonstrate a pulley to the class by laying a broom handle or pole between two desks. Have two children hold the pole steady so that it does not move. Place a rope over the pole, so that the rope is hanging on either side of the pole. Explain to the children that although most pulleys use wheels, it is possible to make a pulley without a wheel. Tell them that the pulley you are making is using the pole as the wheel. Explain that the wheel of the pulley normally makes the rope move more easily, but the pulley you are making works just the same.

Attach an object to one end of the rope and demonstrate how the pulley works. Point out to the children that you don't have to pull the rope straight down. Instead you have the flexibility to pull in a direction that is most comfortable for you. Explain to the children that since the pulley makes it possible to change the direction in which you pull, it makes the job you are performing easier than if you were lifting the object using just your body.

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Second Grade - Science - Lesson 17 - Simple Tools and Machines

Optional Culminating Activity

Objectives

Use simple machines to lift and move a bottle.

Record observations.

Materials

Per group of four

Plastic water or soda bottle, rope, yardstick, blocks

 

Procedure

The students will construct and then use a lever and a pulley to lift a water bottle. Divide the class into groups of four. In each group there should be a Runner, Recorder, Reporter, and Timekeeper. Have the runner pick up the materials for his/her group.

Tell the children that they should first construct a pulley by draping the rope over the back of a chair and follow the directions listed below:

Fill the water bottle halfway with water.

Tie one end of the rope to the neck of the bottle.

Lift the bottle by pulling the other end of the rope.

The timekeeper should keep track of time and keep the group on task and moving along. The recorder should record the group's observations on a piece of notebook paper. Tell the recorder to also write down any problems the group encounters and the solutions the group comes up with.

Next, the groups should construct a lever using the yardstick and blocks to lift the bottle by following the directions listed below:

Place the yardstick under the side of the bottle.

Lay the yardstick over a block.

Lift or move the bottle by pushing down on the other side of the yardstick.

Make sure that the recorder writes down the group's observations for this activity as well as the last. Have each group's reporter share his/her group's observations with the rest of the class.



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Second Grade - Science - Lesson 18 - Elijah McCoy

Objective

Identify the accomplishments of Elijah McCoy.

Suggested Books

McKissack, Patricia and Fredrick McKissack. African-American Inventors. Brookfield, CT: Millbrook Press, 1994.

Towle, Wendy. The Real McCoy: The Life of an African-American Inventor. New York: Scholastic, 1993.

Background Information

Elijah McCoy was born in Ontario, Canada to parents who were runaway slaves from Kentucky. He was the third of twelve children. Elijah's father was a carpenter, but Elijah knew he wanted to be a train engineer, and at the age of fifteen he went to Scotland to study the profession. When he left Scotland he was a master mechanic and engineer and decided to go to the United States. The Civil War had ended and Elijah was able to live in the U.S. as a free man, but no one would hire him as an engineer because he was African American. The only work that he was able to find was a job as a fireman/oilman for the Michigan Central Railroad. As an oilman, Elijah's job was to oil the moving parts of the train. Every few miles, a train had to stop so that the oilman could walk along the outside of the train and put oil on parts of the train so that it would run smoothly on the tracks. While working, Elijah thought about better ways to do his job and he came up with a way to lubricate the train without the train having to stop. His invention was a lubricating cup that automatically dripped oil on the train parts that needed oil. Elijah's automatic oil cup was installed on the Michigan Central Railroad's trains and it was a success.

In his lifetime, Elijah McCoy patented over fifty inventions, none of which was more famous than his automatic oil cup, which eventually became standard equipment on most locomotives and heavy machinery. There were many imitations of McCoy's oil cup, but engineers knew that the model based on McCoy's design was the best of its kind. Hence, they asked for "the real McCoy." This may have been the inspiration for the expression which has come to mean the genuine article or "the real thing."(4)

Elijah McCoy went on to invent many other things including a lawn sprinkler, an ironing board, and about twenty other designs for lubricating devices--a total of fifty-seven patented devices. He died in 1929 at the age of ninety.

Procedure

If possible, read The Real McCoy by Wendy Towle to the children. The book has wonderful illustrations and is a well-written story about Elijah McCoy. If you are unable to obtain this book, you may want to read another good book you know about Elijah McCoy or



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Second Grade - Science - Lesson 18 - Elijah McCoy

read the above background information to the children.

Tell the children that Elijah McCoy's invention of the oil cup was so important because traveling by train was very common during the time that Elijah McCoy lived. Say: There were no cars or planes, so people traveled by train. Even though trains during this time were much slower than the vehicles we are used to traveling in today, trains were faster than the other choices for traveling across land such as on horseback or in a wagon or stagecoach.

Tell the children that the phrase "the real McCoy" is still used today to mean that something is the real thing. Nowadays if you go to a grocery store you can find many generic brands of items you may want to buy. For instance if you want to buy soda you can buy a generic brand of cola or you can buy Coca-Cola brand cola. Although there are many imitations, Coke is considered "the real thing."

Write on the board tennis shoes, computer game systems, and dolls or action figures. Have the children brainstorm names of these products that they would consider to be "the real McCoy." List their suggestions below the respective subjects in a column (possibilities - Nike, Fila, Reebok, Addidas for sneakers; Nintendo, Sega for game systems; Barbie, GI Joe for dolls/action figures). Discuss with the children why they prefer to buy things that they consider the real McCoy (quality and reliability of products). Explain to them that these are the same reasons that the engineers who lived during Elijah McCoy's time asked specifically for McCoy's automatic oil cup because they knew that it was a good product.

1. E. D. Hirsch, ed., What Your Second Grader Needs to Know (New York: Dell, 1991), 295.

2. How Things Work, Childcraft--The How and Why Library, vol. 7 (Chicago: World Book, 1982), 60-61.

3. How Things Work, Childcraft--The How and Why Library, vol. 7 (Chicago: World Book, 1982), 76-77.

4. Wendy Towle. The Real McCoy: The Life of an African-American Inventor. (New York, Scholastic), p. 1.