Grade 2 Science
Core Unit:Magnets

Unit overview:

In this unit students perform a variety of activities to learn about magnets. They determine the kinds of objects which are attracted to a magnet. They also experience the way in which magnets exert a force on some objects at a distance. Other related experiences allow students to discover that there are two poles on a magnet, and that those poles have either attractive or repulsive effects on the pole of a second magnet.

Ensure that each student has an opportunity to work with magnets, observing, making predictions, and recording their results.

Related units:

The grade 1 Core Unit on Motion is related, in that a force is needed to cause motion to occur. Magnetic force is just one of several types of force that could cause an object to move. The grade 1 Optional Unit on Classifying Matter is also related, since students classify objects when learning about magnets by determining whether or not they are attracted to a magnet.

In the grade 2 Core Unit on Weather, related concepts dealing with direction can be developed if students make a compass when learning about magnets. The suggested activities provide one illustration of how this can be done.

The grade 3 Core Unit dealing with Properties of Matter is related. The grade 3 Optional Unit on Simple Machines is also related. Magnets can exert a force on some objects. This force is capable of doing work.

There is an extension of the development of Machines and Work in one of the Optional Units in grade 5.

Suggested themes:

forces, magnetism, magnets, matter, metals, motion

Factors of scientific literacy which should be emphasized:

Common Essential Learnings foundational objectives which should be emphasized:

To develop a contemporary view of technology. (TL)

To promote intuitive and imaginative thought in order to develop the ability to evaluate ideas, processes, experiences, and objects in meaningful contexts. (CCT)

Science foundational and learning objectives:

Investigate magnetism through direct experience.

Predict whether an object will be attracted to a magnet.
Identify objects which can be attracted to magnets.
Identify substances which can be magnetized.
Locate the poles of various types of magnets.
Observe the attraction and repulsion of magnetic poles.
Identify some uses of magnets.
Discover the parts of a magnet where the attraction is the strongest.
Use a compass to determine the direction of the magnetic north pole.

Suggested Activities:

Compile a list of places where magnets are used. Keep updating the list as students discover new uses. Ask students if they have any magnets at home that they could bring to school. (Ifthey have magnets at home, how are they used? Have the students identify some of the ways.) They can experiment with those magnets as well as others in some of the other activities.
Factors: A1, C2, C3, C4, F1, G1, G3
Objectives: 1.3, 1.6
Assessment Techniques: 5, 7, 9
Common Essential Learnings: Technological Literacy. Explore a contemporary view of technology through examining student experiences with magnets around the home (e.g. on refrigerator doors). Emphasize that magnets can be used for all sorts of different things. Magnets help us in many ways.
Place a variety of objects at random at different work stations around the room. Use metal and nonmetal objects in each selection. Have students work in groups. Ask them to record their predictions about which of the objects will be attracted to a magnet. Have them test each object with a magnet, and group the objects in two piles; one for objects attracted to a magnet and another for objects which are not affected by a magnet. Ask them to compare observed results with the predictions made earlier. Have them look for any differences between the objects in the two different groups. List the differences and create a chart.
The activity may be repeated on another occasion, using only metals. This time have the students try to predict and determine which types of metal are attracted to a magnet.
Factors: A1, B2, B5, B7, C2, C3, C4, E3, F1, F2, F3, G1, G2, G3
Objectives: 1.1, 1.2
Assessment Techniques: 3, 8, 9
Common Essential Learnings: Critical and Creative Thinking. The main emphasis in this Core Unit is on performing investigations which allow students to learn about the physical world through direct experience. The predicting and classifying aspects of this activity challenge students to think critically about the nature of the problem being investigated.
Have students lay bar or horseshoe magnets flat on their work area. The initial activity is to determine where on the magnets the strongest and weakest forces are found. They can place a metal paper clip in different places on the magnet, and try to lift the magnet, as a test for the strength of the force on a certain part of the magnet. Or, they may devise their own method for testing the force. Have them record all results by drawing a magnet and colouring in the area on the magnet where the forces are the strongest. Have students share their results with the rest of the class. The sharing helps develop the public nature of science.

The method by which the forces will be measured is not very sensitive. Students will have to make some judgement calls as to where the force begins to drop off in strength. The decrease is more likely to be gradual than abrupt.
As a follow-up, introduce the term "pole." Show students where the poles of a magnet are located. See if the they can establish a relationship between the location of the poles and the strength of the magnetic field near the poles. As a follow-up, be prepared to discuss the poles of the Earth.
Have students pretend they are scientists being interviewed for the evening news. Reinforce the influence of science on our daily lives. Develop a sense of importance for everyone to be knowledgeable about science.
Factors: A1, B2, B5, B7, C2, C3, C4, E3, F1, F3, G1, G2
Objectives: 1.4, 1.7
Assessment Techniques: 3, 5, 7c, 8, 9
Common Essential Learnings: Communication. The activity focuses on understanding through first-hand experiences and the use of language.
The hidden magnet game is an interesting way to show students that a magnet can exert a force at a distance, acting through a material like paper. Tape magnets inside empty milk cartons, or use boxes having different shapes. Use different types of magnets placed in different places in each carton. Tape the cartons shut once the magnets have been secured inside. If the tape does not adhere well to the surface, other adhesives such as FunTac (tm), or other types of containers, such as shoe boxes, could be used. Alternatively, wrap the containers like presents. The point of concealing the magnets is to develop the idea that knowledge can be gathered from indirect evidence.
Number the cartons. Have groups try to find where the magnet is located in each carton. Also, have them try to determine the shape of the magnet. Once a group has finished with a carton, they can pass it on to another group.
Factors: A1, B2, B5, B7, C2, C3, C4, F2, F3, G2
Objectives: 1.1, 1.7
Assessment Techniques: 3, 5, 8
Common Essential Learnings: Personal and Social Values and Skills, Independent Learning. As in other science activities involving directed experience, have students make a habit of recording what they have learned, working cooperatively with others, and sharing their results with the rest of the class. Also, encourage students to share these roles so that everyone gets an opportunity to participate in different ways.

In activities such as this, students begin to see themselves as independent learners within a classroom environment where curiosity is promoted.
Have students rub iron nails with a magnet. They should stroke the nail in one direction, always with the same pole of the magnet. For example, if they grasp the nail by the head, they can stroke it from the head to the tip with the north-seeking pole of a bar magnet. They can then try to see if the nail can pick up small metal objects. Rub the nail a few more times to see if it can pick up more objects.
Other objects which are attracted to a magnet can be magnetized in the same way. Students should also try to magnetize an object which is not attracted to a magnet.
Test the magnetized nail to determine where the north and south- seeking poles are. Students should try to magnetize another nail, using the other pole of the bar magnet, then testing to see how the second nail has become magnetized. Predict and record what might happen to the polarity if the nail were stroked in the opposite direction while being magnetized. Test the prediction. Also, predict what might happen if the magnet was rubbed back and forth along the nail.
Factors: B2, B7, C2, C3, C4, E3, F1, F2, F3, G1, G3
Objectives: 1.2, 1.3
Assessment Techniques: 3, 5, 8
Common Essential Learnings: Critical and Creative Thinking. Students may be able to discover a relationship between the property of being attracted to a magnet and whether a substance can be magnetized. They might also be able to compare the strength of the magnet to the strength obtained by the object which has been magnetized. This need not be explored in any depth, but some students may begin to establish that some relationship exists.
Have the students magnetize a nail, as described in the previous activity. Test that nail to see if it is a magnet. If it is, then use it to magnetize a second nail. Is the second nail a magnet? Can it be used to produce a third nail magnet? Compare the strengths of the magnets produced. Produce two nail magnets of equal strength. Use a clothes pin to hold one in the flame of a candle for 30 seconds. Then compare the strength of the nail magnets. Have the groups that performed the activity report back to share their results with the rest of the class.
Factors: A1, B2, B7, C2, C3, C4, E3, F1, F2, F3, G1, G3
Objectives: 1.1, 1.5,
Assessment Techniques: 3, 5, 8
Common Essential Learnings: Critical and Creative Thinking. In this activity students should make careful observations and share them with others. They should participate in a wide variety of experiences which involve different senses.
Tie a string to each of several magnets, so they are suspended horizontally, free to rotate. Support metre sticks between two desks and hang a magnet from each. Have students observe which way the bar magnets orient themselves once they finally come to rest. Notice in which direction the north-seeking poles of the magnets are aligned. (The bar magnets act like compasses, aligning with the Earth's magnetic field. Be prepared to point this out to students if it is not immediately apparent to them.)
Compare the orientation of the bar magnets in different places in the room. Keep the magnets well separated from each other and away from metal objects. (For example, the metal legs of desks and tables might affect the results.) Place a compass on a flat surface and see which way it is pointing. Compare the way the compass is pointing to the way in which the bar magnets are pointing.
Factors: A1, B2, B7, C2, C3, F1, F2, F3, G1, G3
Objectives: 1.4, 1.5, 1.6, 1.8
Assessment Techniques: 3, 5, 8
Common Essential Learnings: Technological Literacy. A compass is really nothing more than a magnet which is free to rotate in a housing. Using bar magnets to make compasses helps to demystify technology. Basic concepts in science can be extremely useful in helping to understand technology.
Set up a bar magnet hanging from a string, as in the previous activity. Once the bar magnet has come to rest, bring another bar magnet toward it. Try bringing two north-seeking poles together. Repeat using two south-seeking poles in a second trial, and a north- seeking and a south-seeking pole together in a third trial. Record what happens each time. Set up other trials to investigate.
Factors: A1, B2, B7, C2, C3, E3, F1, F2, F3, G1, G3
Objectives: 1.1, 1.2, 1.4, 1.5, 1.6, 1.8
Assessment Techniques: 3, 5, 8, 9
Common Essential Learnings: Critical and Creative Thinking. Students should be able to analyze the results of this activity to come up with a generalization governing the attraction of unlike magnetic poles and the repulsion of similar magnetic poles. Develop a poster summarizing the generalizations that have been made.
Set up an activity centre, at which students test substances to determine if a magnet can attract something through the substance. For example, if a piece of paper is held between a magnet and a paper clip, can the magnet still attract the paper clip? If ten sheets of paper are between the magnet and the paper clip, can the magnet still attract? Other substances to test might be such things as plastic drinking cups, wax paper, aluminum foil, and so on. The magnet may attract through some of them, but not through others. Have students report their findings back to the entire class.
Factors: A1, B2, B5, B7, C2, C3, C4, E3, F1, F2, F3, G1, G2, G3
Objectives: 1.1, 1.2, 1.7
Assessment Techniques: 3, 4, 5, 8
Common Essential Learnings: Independent Learning. The activity can be set up in other ways, but the activity centre allows students to work independently while the rest of the class may be working on other things. Students can work individually or in small groups. Learning can become self-directed at the activity centre. The activity offers a model for independent learning which students might be able to undertake on their own in other ways.
Brainstorm to develop a list of things that can be attracted to a magnet and another list of things that can not be attracted to a magnet. For all of the objects listed, assign one to each student and have them draw a picture of the object on construction paper and cut it out. On the objects that can be attracted to a magnet, attach a metal paper clip to one corner.

Place all of the cut-outs into a box. Attach a magnet to a string and tie the string to a metre stick. Use this to play fishpond. Have some students go to the fishpond and pull out objects. The objects which are attracted to magnets will be pulled out of the pond. This can serve as an interesting method for drill and review.
Factors: A1, B2, B7, C2, C3, C4, E3, F1, F3, G1, G2
Objectives: 1.1, 1.2, 1.6
Assessment Techniques: 1, 5, 8
Common Essential Learnings: Critical and Creative Thinking. Drill and practice exercises can be highly motivating, if they are approached in a slightly different manner. The "fish pond" in this activity serves to illustrate this.
Other activities which allow students to observe what type of objects are attracted to a magnet should also be performed. Some debate may arise as to whether certain objects can or can not be attracted to a magnet. For example, some coins or some keys are attracted to magnets, while others are not. Students need to be made aware that it is not the type of object which determines if it will be attracted to a magnet. Rather, the type of material from which the object is made is the important factor.
Build a magnetic kite by suspending a magnet from 50 cm to 80 cm above a flat surface. This can be done by taping the magnet just slightly beyond the edge of a desk. Tie a paper clip to a 1 m long piece of string. Tape the string to a surface directly underneath the magnet, so that the paper clip will be close enough to the magnet to be held in its field, without touching the magnet. Experiment to get the greatest separation which will produce the best visual effect. This can be related to activity 9, by placing paper between the magnet and the paper clip to see if the magnet flag still remains suspended.
Factors: A1, B2, B7, C2, C3, E3, F1, G1, G2
Objectives: 1.1, 1.6, 1.7
Assessment Techniques: 4, 5, 8
Common Essential Learnings: Technological Literacy. Students have the opportunity to explore the relationships between natural and constructed situations. They are involved in the construction of device which has to meet certain specifications. Although the device may appear to serve no useful purpose, students may be able to suggest some ways in which it might be put to good use.
Place a small magnet on a flat piece of styrofoam. This could be cut from a meat tray. (Note: The use of styrofoam is being questioned because of its environmental impact. If suitable alternative materials can be found, they should be used instead.) Make sure that you orient the magnet so that the poles are not pointing up and down, but so that the line between the poles is horizontal. (Disc magnets do not work well for this activity.) Float the styrofoam in an aluminum, plastic, or glass tray. Watch how the magnet orients itself. Compare it to the way in which the needle on a compass points. Make sure there are no metal objects (other than the aluminum tray) near the magnets used in this activity.

As a follow-up, suggest that the first compasses, used for navigation on ships, were constructed in a similar way, using large pieces of loadstone, a mineral which is naturally magnetic.
Factors: A1, B2, B5, B7, C2, C3, E3, F1, F2, F3, G1, G3
Objectives: 1.4, 1.6, 1.8
Assessment Techniques: 3, 5, 8
Common Essential Learnings: Technological Literacy. This activity allows students to explore the evolution of technological advances, particularly if the follow-up in which the historical uses of compasses in navigation is discussed. The follow-up also serves as an effective way to branch into Social Studies by considering explorers, where they came from, how they travelled, and how they were able to navigate from one place to another. The use of other techniques for navigation could be discussed as a follow-up.
Suspend a magnet (disc magnets work best here) from a string which is about a metre long so that it hangs about 1 cm to 2 cm above a flat surface. Place other magnets on the surface near the rest point of the suspended magnet. Swing the magnet on the string and watch the interaction of the fields of the suspended magnet and the stationary ones. Move the magnets on the surface to different positions, to produce different effects on the suspended magnet.
Factors: A1, B2, B5, B7, C2, C3, E3, F1, F2, G1, G2
Objectives: 1.1, 1.2, 1.4, 1.5, 1.7
Assessment Techniques: 3, 5, 8
Common Essential Learnings: Technological Literacy, Independent Learning. The device serves to amuse and to fascinate. Have students try to predict the way in which the swinging magnet will move when the magnets on the flat surface are re-arranged.
Some students might begin to wonder if the swinging magnet will keep swinging indefinitely. Set it up and allow them to observe what happens. While they may not be ready to explore the concept of a perpetual motion machine at this age, setting up a situation which illustrates clearly that perpetual motion can not occur, is good preparation for physical science activities that follow in later years.
Test some disc magnets with cardboard to determine if their field can penetrate a thin piece of cardboard. If they are strong enough, tape some to one side of the cardboard. Place one end of the cardboard on several books to form a ramp with the magnets on the underside of the cardboard. If necessary, support the edges of the cardboard with rulers or metre sticks to prevent sagging. Run some steel ball bearings down the ramp to observe the effect of the magnets on the path the bearings take.

Set up another ramp beforehand, so that students are unable to see how the magnets are arranged underneath. Ask them to predict how the ball will roll when it is released from the top of the ramp. As the ball rolls down the ramp and interacts with the magnets below, it will undergo motion which will not likely be anticipated. (Rolling a glass marble down the ramp may serve as a useful reference for comparison. The glass marble will roll without being deflected by the magnetic field.) Repeat several trials. Ask the students to suggest what is unusual about the way in which the ball is rolling, and what might be causing it. (Since they can not see under the ramp, there is no right answer as to what might be causing the erratic motion. However, some answers may be more easily justified than others based on supporting evidence.) Ask the students to think of other nondestructive tests (that is, without looking under the ramp) that could be performed to test their ideas about what may be causing the unusual motion of the ball.
Factors: A1, B2, B5, B7, C2, C3, E3, F1, F2, F3, G1, G3
Objectives: 1.1, 1.4, 1.7
Assessment Techniques: 3, 5, 8, 9
Common Essential Learnings: Critical and Creative Thinking. The activity serves as a model to illustrate several important things about the nature of science. The observations made involve obtaining indirect evidence. Often in science one can only observe effects rather than the actual thing one wishes to investigate. Students will encounter similar situations in later years.
Make a recording on an audio cassette. Play the cassette. Run a strong magnet back and forth directly above the tape without touching it. Play the cassette again. Ask for hypotheses about what happened. Play a record from a record player. Run a magnet back and forth above the surface of the record. (Do not scratch the record by touching it.) Play the record again. Ask for a hypothesis about records and cassettes.

Similarly, copy a self-booting computer program to a scratch diskette. (The recording on the scratch diskette will be erased. Make sure there are back-up copies available) Execute the program. Run the magnet over the surface of the scratch diskette without making direct contact. Try to execute the program again. Ask for a hypothesis about how the recording of information on computer diskettes compares to that on cassettes and records.

What would happen if a videotape were used in this activity? Predict and experiment to find out.
Factors: A1, B2, B5, C2, C3, E3, F1, F2, F3, G1, G3
Objectives: 1.1, 1.3, 1.6
Assessment Techniques: 3, 5, 8
Common Essential Learnings: Technological Literacy, Critical and Creative Thinking. This is a good activity to show how the principles of magnetism are applied in the technology of recording devices such as computer diskettes and cassette tapes. A metallic layer in a thin film is capable of being magnetized on these types of recording media. The heads of the recording device produce a strong magnetic field which magnetizes the tape or disk. Playing back the recording involves reading the information from the magnetic fields on the tape or disk.
Make small two-dimensional puppet characters to illustrate a story or a poem. Tape or glue a magnet to the back of each puppet. Draw a background scene for the story on a sheet of thin cardboard. Place the puppets on the cardboard in such a way that the cardboard can be supported with a few students able to work the puppets with other magnets. Have the students move the puppets to where they have to go during different parts of the story. It might be easier if the students working the puppets from behind had a tracing of the things on the cardboard background scene on the back of the cardboard as well, in order that they would have a better idea of where to place the characters.
Some of the students in the class can take turns reading parts of the story while others watch the story unfold in the puppet show. As with other puppet shows, the effect is more dramatic if the puppeteers are out of view of the audience.
Extend this into other interesting English Language Arts activities. Using different puppets on a different background scene, move the puppets about in the same way using the magnets. Once students have seen the puppets moving about, they would have to say what happened in the story.
Factors: A1, B2, B5, B7, C2, C3, C4, E3, F1, F2, G1, G3
Objectives: 1.2, 1.5, 1.6, 1.7
Assessment Techniques: 1, 2, 3, 4, 5
Common Essential Learnings: Technological Literacy. Often an understanding of a particular technology leads to many interesting applications. This activity illustrates how an understanding of science concepts, and a development of a technological device which can be used to manipulate objects at a distance, can lead to an interesting application in the arts and entertainment. This helps to show one way in which technology can be used to enhance the quality of life and to offer creative opportunities which may be more effective than if conventional means were used.
It also illustrates how technology can be used to enhance the imagination and to stimulate further learning. The technology used in this activity is not the centre of attention. It acts "behind the scenes" as it were. It can be regarded as a means to an end rather than as an end unto itself.

Grade 2 Science Core Unit:Magnets