Lego Levers

LEGO Dada is the fi tt l ea tge ted i v i s i on of LEGO Systems06'0decta 9 6 2 2

LEGO DACTA®Lever Set

Contents

Activities

Objectives

2

Introduction

This booklet has been developed by teachers to supportand guide you and your students through your explorationof the LEGO DACTA Lever Set, #9612.The booklet contains:• Information about levers• Simple hands-on lever activities• Drawings of possible solutions

Activities for exploring concepts (pages 3-7), investigatingprinciples (pages 9-11), and solving problems (pages 12-15)are included for elementary school students of varyingabilities. The activities foster and enhance cooperativelearning in teams of two students per building set.

After performing the activities in this booklet,students will be able to:• Define a lever as a rod or arm that tilts around a pivotto produce useful motion.• Describe the fulcrum, effort, and load (or resistance)of a lever.▪ Build models of devices which incorporate threedifferent classes (or types) of levers.• Recognize that the effectiveness of a lever dependson the arrangement of the fulcrum, effort, and load.• Have fun with levers!

LEGO and D AC TA are tradmalks o ld ie LEG( ) Group.Dis [tibuted by the LEGOGroup. DK-7190 Ba w d , Dcmnark.0 1997 The LEGG Group, ISBN 0-91453I-83-C.

Building Element Survey0 6 each, I x 2 beam, red

2 each, 1 x 4 beam, red



1 each, 2 x 6 weighted brick (54 grams), black

6 each, connector peg, gray

O r 10 each, friction connector peg, black

0 8 each, bushing, gray

0 0 '0 2 each, axle 4 studs long, black

c 1,04A° I each, axle 6 studs long, black

r t t 2 each, I x 2 plate, yellow

e 2 each, 1 x 3 plate, yellow

2 each, 1 x 6 plate, yellow



li t is tan .ao,o, • • 1 each, 4 x 4 plate, yellow

0 4 each, 2 x 2 flat tile, yellow

1 I each, 2 x 2 angular plate, redC D 1 each, rubber band, black

18 =

Levers in ActionA lever is a rod or arm that tilts around aopivot to produce useful motion. One of the tisimple machines, the lever can make work 0easier by amplifying motion or force, 6or by changing the direction of a force. a

Here are some examples of levers or devicesmade up of levers,The three classes of levers are discussed onpages 4-7.

Seesaw (1st class),• Scissors (connected 1st c1ass)-3• Wheelbarrow (2nd class),3• Nutcracker (connected 2nd class)e3• Fishing rod (3rd class) .q111 Tweezers (connected 3rd class))• Nail clippers (2nd class and 0connected 3rd class)

Photographs on the back of this bookletshow other examples of how levers makework easier.

The diagram at the lower right shows thevarious parts of a lever in general.

The load is moved by the effort (a push or 0pull) making the lever tilt about the fulcrum 0(pivot).

Familiarize yourself with levers by workingthrough activities on pages 4-7. Photocopythe drawings on pages 16-17 for easyreference. You may wish to provide theseactivities to your students as well.

Fulcrum

EffortLoad

,

3

Levers in ActionFirst Class Lever• Build the base and model 1 shown onpage 16. Predict what happens when you11122 down at t _ l i e e l l o N 1 the handle.As you push down (effort), the beamtilts about the axle (fulcrum) and lifts theweighted brick (load).

• Predict what hap ens w S l idown on the handle closer to the fulcrum._You also Igt the weighted brick, but youhave to push down with more force,

Main Ideas:A first class lever has the fulcrum betweenthe effort and the load. I t is easier to lif ta load with a first class lever if you pushdown at a point far from the fulcrum.

Additional Information:First class levers are oftenused to change the directionof forces. A seesaw is anexample of a first class lever.First class levers can also beconnected to each other, as ina pair of scissors.

effo

Extension:Switch the places of the yellow tile andthe weighted brick. Repeat the aboveinvestigation. Then change the lontionof the brick along the beam. ( A ) ' A t e t a a(It takes a great effort to raise the brick, becauseyou are pushing down so close to the fulttum.However, as the load is also moved closer to thefulcrum, the effort needed becomes less.)

O r

2 Second Class Lever

3 Ilird Class Lever

4 J ca, . MAY BE P HO TO CO P IE D FOR STUDENT R EF ER EN CE 17

Lever Concept Models

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MAY BE PHOTOCOPIED FOR STUDENT REFERENCE

Levers in ActionSecond Class Lever• Build model 2 shown on page 17.Predict what happens when you push up_althe yellow tile on the handk.As you push up (effort), the beam tilts aboutthe axle (fulcrum) and lifts the weightedbrick (load).

• Predict what happens when you push upon the handle closer to the fulcrum.You also lift the weighted brick, but youhave to push up with more force.

Main Ideas:A second class lever has the load betweenthe fulcrum and the effort. The effort willalways be less than the load. The fartherfrom the fulcrum you apply the effort,the easier it is to lift the load.

Additional Information:Second class levers are often used to liftheavy loads or to apply large forces.A wheelbarrow is a typical example of asecond class lever. Second class levers canalso be connected to each other, as in anutcracker.

) Extension:Move the weighted brick closer to the

yellow tile and r e p t ttk a b l s p r e

-investigation. L O(it takes more effort to raise theload as it is moved further fromthe fulcrum. When the load is closestto the fulcrum, it can be lifted withthe least effort.)

fulcrum

R OT

•ts

load

w = r 1 = 4- ,; , .4 :# 1 0 #. )- 4

effort

4

5

Levers in Action

6

Third Class Lever• Build model 3 shown on page 17.Predict what happens when you push up onthe handle at the yellow tile.As you push up (effort), the beam tilts aboutthe axle (fulcrum) and lifts the weightedbrick (load).

( ) • Predict what happens when you push upon the handle closer to the fulcrum.You also lift7he weighted brick, but youhave to push up with more force.

Main Ideas:A third class lever has the effort betweenthe fulcrum and the load. The fartherf rom the fulcrum the load is located,the more effort you will have to applyto lif t it.

Additional Information:Although third class levers can be used tolif t loads or apply specific forces, as in astapler, they are also used to amplifymotion. A fishing rod is a typical example.The fulcrum is the hand at the end of the rodhandle. A small motion of your other handproduces a large movement of the rod tip.

Third class levers can also beconnected to each other, as in apair of tweezers.

fulcrumload

Notes for: Cow ControlBuilding Hints

Extra MaterialsTesting the Solution

Extension

In the sample solution below on the left, note the counter-weight (extra beams and plates at the right end of thebarrier beam). When you push down on the counter-weight, the beam acts as a first class lever and raises upeasily. The two axles shown can be used to lock the barrierin the raised and in the lowered positions.

When you raise the barrier beam as shown in the drawingon the right, the beam acts as a second class lever.

Students may want to use small animal figures.

Does the barrier lock in both the raised and the loweredpositions?

Judge how easily the barrier can be operated.

Change the device so that the barrier is as long aspossible.

Counterweight

15

Cow Control

Linda needs a way to control the cows asthey cross the railroad on their way intothe barnyard.

Design and build a lever device which:

• can keep the cows from crossingthe railroad tracks.

• can be raised and lowered.

• can be locked in the raised andthe lowered position.

14 P R O B L E M SOLVING COPYMASTER 2

Levers in ActionLever SummaryFirst Class LeversThe fulcrum is between the effort and theload. A seesaw is an example of a simplefirst class lever. A pair of scissors is anexample of two connected first class levers.

Second Class LeversThe load is between the fulcrum and theeffort. A wheelbarrow is an example of asimple second class lever. A nutcracker is anexample of two connected second classlevers.

Third Class LeversThe effort is between the fulcrum and theload. A stapler or a fishing rod is anexample of a simple third class lever.A pair of tweezers is an example of twoconnected third class levers.

Force and EffortTo lift a load with the least effort:

• place the load as close to thefulcrum as possible.

• apply the effort as far fromthe fulcrum as possible.

First ClassLever

Second ClassLever

load f u l c r um e f f o r t

fulcium

Third Class Lever

load effort

load effort f u l c r u m

7

AssessmentExamples of Levers

Process and InquirySkills

Critical ThinkingSkills

MeasuringProblem SolvingInferringCommunicating

Cause and effectPredictingObservingHypothesizing

May be photocopied for student work. See page 3.

Gathering and recalling informationUnderstanding and interpreting data and informationApplying what is learned to solve problems in new

situationsAnalyzing a problem into its component partsSynthesizing various aspects or components into a new

whole to solve a problemEvaluating one's own wort

Notes for: Reach OutBuilding Hints

Extra Materials

Testing the Solution

Extension

A series of connected levers works well for this problem.Sample solutions are shown below. Students might want touse a rubber band to keep the pincers open or closed.

Students can make use of extra rubber bands, string,and assorted small objects.

Can the weighted brick be picked up?

Judge how easily the device can be operated with onehand.

Modify the device so it can pick up a sheet of paper,

8 1 3

Reach Out

Aunt Monica has dropped her glassesand is having difficulty pickingthem up. She needs some help.

Design and build a picker-upper which:

• can be operated with one hand.

• can pick up the weighted brick.

12 P R O B L E M SOLVING COPYMASTER I

Notes for Building Card IStudents can investigate connected first and third class leversusing Building Card I from their Lever Set.

Instructions for your students appear below. Answers are shownin parentheses.

Build the model of the pliers through step 2.

• How does this model use levers?(Two first class levers are connected to a common fulcrum.The effort is applied at the ends of the handles. The load ispicked up by the other ends.)

• Use the model to pick up several different objects. Gentlypinch your finger with the model to feel how much force it canapply. Easy does it!

• Change the position of the connector peg in the modelas shown in step 2A and repeat your investigation. How is thismodel different?(This model can apply a little more force because the fulcrum iscloser to the load.)

• Move the connector peg to the ends of the handles as shownin step 2B and repeat your investigation. How does this modeluse levers?(Two third class levers are connected to a common fulcrum at

the ends of the handles. The load is picked up by the other endsand the effort is applied in between. This model applies lessforce because the load is far from the fulcrum.)

• Build the model shown in step 2C on your card. This modelconsists of two pairs of connected first class levers. Use themodel to pick up several different objects. How far can it reach?

• Build the model in step 2D, adding the dragon parts as shown(see page 18), Predict what happens when the model isoperated. (The jaws and tail move.) Invite students todesign and color a dragon body to add to the model.

( 4 /4 9

Notes for Building Card 2 B u i l d i n g Card Extensions IdeasStudents can investigate first and second class levers usingBuilding Card 2 from their Lever Set.


Build the first model, following the instructions throughstep 6. How does this model use levers?(A first class lever is attached to an upright beam with a trayon top. Other beams parallel to the lever keep the tray upright.)

• Predict what happens if you place a small object on the tray.Then test your prediction with several different objects.(The object (effort) makes the tray sink down, The other end(load) of the long beam rises. The heavier the object, the higherthe long beam rises.)

• How can this model be used?(The model could compare the weights of different objects.)

• Change your model as shown in step 6A by adding theweighted brick to the end of the long beam and attaching acardboard scale (see page 18) to the upright beam. Predict whathappens if you place a small object on the tray. Then test yourprediction with several different objects.(The device still functions as above. The beam does not rise ashigh for the objects used earlier because their weight does notpush down enough to raise the weighted brick as much.)

• How can this model be used?(This model can be used to compare the weights of heavier

objects. Different cardboard scales could be designed todetermine the weight of objects.)

• Change your device into a press as shown in step 613.How does the press use a lever?(When you pull down (effort) on the handle, the beam pushesdown (load) to press the base. This is a second class lever.)How could the press be used?(Students can suggest many uses, including pressing plates ontoother beams.)

10

Building Card IWhat other animals or figures could your students inventfor the model in step 2D? Set up a display to show off thework of your imaginative students.

Convert the skeleton of the model in step 2D intoa weighing device to lead into Building Card 2.Place the weighted brick as shown in the drawingon the right. Test the device withseveral small objects.

Ask each of your students to construct asimple pair of "scissors" using two long beamsand one gray connector peg. Challengestudents to find a way to connect their modelstogether end to end to make a super-long extender,How far will it reach? What will it pick-up?

Building Card 2Suggest that groups of students use two devicesfrom step 6 together to weigh objects. Challengethem to predict what happens if they place ayardstick or meter stick across the trays of two devicesat once.(if the stick is supported at the ends, each device willsupport half the weight. I f one of the devices is movednearer the middle of the stick, it will support more of theweight)

Invite students to use their device from step 6 B as acatapult to launch balls of paper. How consistently canthey flip their paper balls into the trash can?What class of lever is the catapult?(The catapult is a first class lever The rubber bandprovides the effort, and the ball is the load.)

ty"

Notes for Building Card 2 B u i l d i n g Card Extensions IdeasStudents can investigate first and second class levers usingBuilding Card 2 from their Lever Set.


Build the first model, following the instructions throughstep 6. How does this model use levers?(A first class lever is attached to an upright beam with a trayon top. Other beams parallel to the lever keep the tray upright.)

• Predict what happens if you place a small object on the tray.Then test your prediction with several different objects.(The object (effort) makes the tray sink down, The other end(load) of the long beam rises. The heavier the object, the higherthe long beam rises.)

• How can this model be used?(The model could compare the weights of different objects.)

• Change your model as shown in step 6A by adding theweighted brick to the end of the long beam and attaching acardboard scale (see page 18) to the upright beam. Predict whathappens if you place a small object on the tray. Then test yourprediction with several different objects.(The device still functions as above. The beam does not rise ashigh for the objects used earlier because their weight does notpush down enough to raise the weighted brick as much.)

• How can this model be used?(This model can be used to compare the weights of heavier

objects. Different cardboard scales could be designed todetermine the weight of objects.)

• Change your device into a press as shown in step 613.How does the press use a lever?(When you pull down (effort) on the handle, the beam pushesdown (load) to press the base. This is a second class lever.)How could the press be used?(Students can suggest many uses, including pressing plates ontoother beams.)

10

Building Card IWhat other animals or figures could your students inventfor the model in step 2D? Set up a display to show off thework of your imaginative students.

Convert the skeleton of the model in step 2D intoa weighing device to lead into Building Card 2.Place the weighted brick as shown in the drawingon the right. Test the device withseveral small objects.

Ask each of your students to construct asimple pair of "scissors" using two long beamsand one gray connector peg. Challengestudents to find a way to connect their modelstogether end to end to make a super-long extender,How far will it reach? What will it pick-up?

Building Card 2Suggest that groups of students use two devicesfrom step 6 together to weigh objects. Challengethem to predict what happens if they place ayardstick or meter stick across the trays of two devicesat once.(if the stick is supported at the ends, each device willsupport half the weight. I f one of the devices is movednearer the middle of the stick, it will support more of theweight)

Invite students to use their device from step 6 B as acatapult to launch balls of paper. How consistently canthey flip their paper balls into the trash can?What class of lever is the catapult?(The catapult is a first class lever The rubber bandprovides the effort, and the ball is the load.)

ty"

Reach Out

Aunt Monica has dropped her glassesand is having difficulty pickingthem up. She needs some help.

Design and build a picker-upper which:

• can be operated with one hand.

• can pick up the weighted brick.

12 P R O B L E M SOLVING COPYMASTER I

Notes for Building Card IStudents can investigate connected first and third class leversusing Building Card I from their Lever Set.


Build the model of the pliers through step 2.

• How does this model use levers?(Two first class levers are connected to a common fulcrum.The effort is applied at the ends of the handles. The load ispicked up by the other ends.)

• Use the model to pick up several different objects. Gentlypinch your finger with the model to feel how much force it canapply. Easy does it!

• Change the position of the connector peg in the modelas shown in step 2A and repeat your investigation. How is thismodel different?(This model can apply a little more force because the fulcrum iscloser to the load.)

• Move the connector peg to the ends of the handles as shownin step 2B and repeat your investigation. How does this modeluse levers?(Two third class levers are connected to a common fulcrum at

the ends of the handles. The load is picked up by the other endsand the effort is applied in between. This model applies lessforce because the load is far from the fulcrum.)

• Build the model shown in step 2C on your card. This modelconsists of two pairs of connected first class levers. Use themodel to pick up several different objects. How far can it reach?

• Build the model in step 2D, adding the dragon parts as shown(see page 18), Predict what happens when the model isoperated. (The jaws and tail move.) Invite students todesign and color a dragon body to add to the model.

( 4 /4 9

AssessmentExamples of Levers

Process and InquirySkills

Critical ThinkingSkills

MeasuringProblem SolvingInferringCommunicating

Cause and effectPredictingObservingHypothesizing

May be photocopied for student work. See page 3.

Gathering and recalling informationUnderstanding and interpreting data and informationApplying what is learned to solve problems in new

situationsAnalyzing a problem into its component partsSynthesizing various aspects or components into a new

whole to solve a problemEvaluating one's own wort

Notes for: Reach OutBuilding Hints

Extra Materials

Testing the Solution

Extension

A series of connected levers works well for this problem.Sample solutions are shown below. Students might want touse a rubber band to keep the pincers open or closed.

Students can make use of extra rubber bands, string,and assorted small objects.

Can the weighted brick be picked up?

Judge how easily the device can be operated with onehand.

Modify the device so it can pick up a sheet of paper,

8 1 3

Cow Control

Linda needs a way to control the cows asthey cross the railroad on their way intothe barnyard.

Design and build a lever device which:

• can keep the cows from crossingthe railroad tracks.

• can be raised and lowered.

• can be locked in the raised andthe lowered position.

14 P R O B L E M SOLVING COPYMASTER 2

Levers in ActionLever SummaryFirst Class LeversThe fulcrum is between the effort and theload. A seesaw is an example of a simplefirst class lever. A pair of scissors is anexample of two connected first class levers.

Second Class LeversThe load is between the fulcrum and theeffort. A wheelbarrow is an example of asimple second class lever. A nutcracker is anexample of two connected second classlevers.

Third Class LeversThe effort is between the fulcrum and theload. A stapler or a fishing rod is anexample of a simple third class lever.A pair of tweezers is an example of twoconnected third class levers.

Force and EffortTo lift a load with the least effort:

• place the load as close to thefulcrum as possible.

• apply the effort as far fromthe fulcrum as possible.

First ClassLever

Second ClassLever

load f u l c r um e f f o r t

fulcium

Third Class Lever

load effort

load effort f u l c r u m

7

Levers in Action

6

Third Class Lever• Build model 3 shown on page 17.Predict what happens when you push up onthe handle at the yellow tile.As you push up (effort), the beam tilts aboutthe axle (fulcrum) and lifts the weightedbrick (load).

( ) • Predict what happens when you push upon the handle closer to the fulcrum.You also lift7he weighted brick, but youhave to push up with more force.

Main Ideas:A third class lever has the effort betweenthe fulcrum and the load. The fartherf rom the fulcrum the load is located,the more effort you will have to applyto lif t it.

Additional Information:Although third class levers can be used tolif t loads or apply specific forces, as in astapler, they are also used to amplifymotion. A fishing rod is a typical example.The fulcrum is the hand at the end of the rodhandle. A small motion of your other handproduces a large movement of the rod tip.

Third class levers can also beconnected to each other, as in apair of tweezers.

fulcrumload

Notes for: Cow ControlBuilding Hints

Extra MaterialsTesting the Solution

Extension

In the sample solution below on the left, note the counter-weight (extra beams and plates at the right end of thebarrier beam). When you push down on the counter-weight, the beam acts as a first class lever and raises upeasily. The two axles shown can be used to lock the barrierin the raised and in the lowered positions.

When you raise the barrier beam as shown in the drawingon the right, the beam acts as a second class lever.

Students may want to use small animal figures.

Does the barrier lock in both the raised and the loweredpositions?

Judge how easily the barrier can be operated.

Change the device so that the barrier is as long aspossible.

Counterweight

15

Lever Concept Models

P iarcal• W

M R ,1 ,tin

• -•c•Ru ll aw. i• •• •• ••,ww,mi rt ewmoh .o-•a .

4 0 , 1 • • ••- • A P.Ne t Koa,r0 -. . .1 0 1 0 1 1 .0 • 0 1 , 8 ," .

opim elem 4141w w , I r t- 1• 0,0 1 0 . 4 . 4 1 1 1 1 5 , 4

Im o n w 4 E 1 /W• 1 • S t, e l f • . 0 1 . 1 . # . 1 , 0 1 • • • . •

. 1 0 , , • • • • • 1 1 ,1 • N ,O W 1,P 4,012.41M A S • • • 01 1 ,., 1 0.1 . •1•1 1ra p,CW 111,• l aa r il i a6 ,

kari • W n t m . 1 0 1 % . . . . f r a p l . . . 1 . h n t • O nw

i leattelmiklaldeld.17,4•11.1-11011.10.1. .ag

• • • • • • •,r1,

4 / te .a t t l e a l l • P WW3

e l a w k a t..! . . 1 4 , . • 1 4 , 0 1 , 1 0 , 1 0 • • , • • • •90• 7,14P A C IP O W,P rrn1W.09,0• 0000,11.100.• • - •

P itilliA bol.101k I O W• 1.1.,o114,0 g ra i t l i k r s • , . . •• , ,qgliAl .. .1.• 14• •• •••PO,V ,• •• ,,• •• 1

p e p . ,INiS1.40•1“1.111,Ifitil

,I• 4114• 04 ,• .% la •

q1•10•610HAEVyket ...qr.,. 1.611th,,,ppeem v•tilh,

s*,,,smanou.,ona•voiwito•4*-Prierefig loorte•er.-A1--

. 1 t • f r a r a n m

-1143,44

Flrs: Class Lever

16

r• H •01 1 .1,1 1 11 11 1 .11 1 1 0• V

00nO prptiMmon 1.. .1 M k M i l •

•••• r 0 , 1 0 • • • • • •

s a t i t i l in iT h . S h's " . • , , m 1 . 4 401 . ' " 1 " *: . 4 0 . . . 4, 1 1 " " t n. . r. " 'SM I WO O S

S t e t w i t i r i , s g-tooti... ignts it iegyar_241Mmt

I l i c o a s m . s . t e“ •-• 0 1 . 0 -E s i w t . w e t rte r4 " "1".

maginak t ra . . osaw,”o"Ps , ,pat ta.MAI /a.k .So_,04111.0

!SS Wath•vor,,,,,,,,,..

P lif r”1 1101. r.b t/t 1.1 11E le

_ Wa t t P0,1 • 1 " / "

Algan*WPIAP0 . 4 • • • • •

MAY BE PHOTOCOPIED FOR STUDENT REFERENCE

Levers in ActionSecond Class Lever• Build model 2 shown on page 17.Predict what happens when you push up_althe yellow tile on the handk.As you push up (effort), the beam tilts aboutthe axle (fulcrum) and lifts the weightedbrick (load).

• Predict what happens when you push upon the handle closer to the fulcrum.You also lift the weighted brick, but youhave to push up with more force.

Main Ideas:A second class lever has the load betweenthe fulcrum and the effort. The effort willalways be less than the load. The fartherfrom the fulcrum you apply the effort,the easier it is to lift the load.

Additional Information:Second class levers are often used to liftheavy loads or to apply large forces.A wheelbarrow is a typical example of asecond class lever. Second class levers canalso be connected to each other, as in anutcracker.

) Extension:Move the weighted brick closer to the

yellow tile and r e p t ttk a b l s p r e

-investigation. L O(it takes more effort to raise theload as it is moved further fromthe fulcrum. When the load is closestto the fulcrum, it can be lifted withthe least effort.)

fulcrum

R OT

•ts

load

w = r 1 = 4- ,; , .4 :# 1 0 #. )- 4

effort

4

5

Levers in ActionFirst Class Lever• Build the base and model 1 shown onpage 16. Predict what happens when you11122 down at t _ l i e e l l o N 1 the handle.As you push down (effort), the beamtilts about the axle (fulcrum) and lifts theweighted brick (load).

• Predict what hap ens w S l idown on the handle closer to the fulcrum._You also Igt the weighted brick, but youhave to push down with more force,

Main Ideas:A first class lever has the fulcrum betweenthe effort and the load. I t is easier to lif ta load with a first class lever if you pushdown at a point far from the fulcrum.

Additional Information:First class levers are oftenused to change the directionof forces. A seesaw is anexample of a first class lever.First class levers can also beconnected to each other, as ina pair of scissors.

effo

Extension:Switch the places of the yellow tile andthe weighted brick. Repeat the aboveinvestigation. Then change the lontionof the brick along the beam. ( A ) ' A t e t a a(It takes a great effort to raise the brick, becauseyou are pushing down so close to the fulttum.However, as the load is also moved closer to thefulcrum, the effort needed becomes less.)

O r

2 Second Class Lever

3 Ilird Class Lever

4 J ca, . MAY BE P HO TO CO P IE D FOR STUDENT R EF ER EN CE 17

18 =

Levers in ActionA lever is a rod or arm that tilts around aopivot to produce useful motion. One of the tisimple machines, the lever can make work 0easier by amplifying motion or force, 6or by changing the direction of a force. a

Here are some examples of levers or devicesmade up of levers,The three classes of levers are discussed onpages 4-7.

Seesaw (1st class),• Scissors (connected 1st c1ass)-3• Wheelbarrow (2nd class),3• Nutcracker (connected 2nd class)e3• Fishing rod (3rd class) .q111 Tweezers (connected 3rd class))• Nail clippers (2nd class and 0connected 3rd class)

Photographs on the back of this bookletshow other examples of how levers makework easier.

The diagram at the lower right shows thevarious parts of a lever in general.

The load is moved by the effort (a push or 0pull) making the lever tilt about the fulcrum 0(pivot).

Familiarize yourself with levers by workingthrough activities on pages 4-7. Photocopythe drawings on pages 16-17 for easyreference. You may wish to provide theseactivities to your students as well.

Fulcrum

EffortLoad

,

3

LEGO DACTA®Lever Set

Contents

Activities

Objectives

2

Introduction

This booklet has been developed by teachers to supportand guide you and your students through your explorationof the LEGO DACTA Lever Set, #9612.The booklet contains:• Information about levers• Simple hands-on lever activities• Drawings of possible solutions

Activities for exploring concepts (pages 3-7), investigatingprinciples (pages 9-11), and solving problems (pages 12-15)are included for elementary school students of varyingabilities. The activities foster and enhance cooperativelearning in teams of two students per building set.

After performing the activities in this booklet,students will be able to:• Define a lever as a rod or arm that tilts around a pivotto produce useful motion.• Describe the fulcrum, effort, and load (or resistance)of a lever.▪ Build models of devices which incorporate threedifferent classes (or types) of levers.• Recognize that the effectiveness of a lever dependson the arrangement of the fulcrum, effort, and load.• Have fun with levers!

LEGO and D AC TA are tradmalks o ld ie LEG( ) Group.Dis [tibuted by the LEGOGroup. DK-7190 Ba w d , Dcmnark.0 1997 The LEGG Group, ISBN 0-91453I-83-C.

Building Element Survey0 6 each, I x 2 beam, red




1 each, 2 x 6 weighted brick (54 grams), black

6 each, connector peg, gray

O r 10 each, friction connector peg, black

0 8 each, bushing, gray

0 0 '0 2 each, axle 4 studs long, black

c 1,04A° I each, axle 6 studs long, black

r t t 2 each, I x 2 plate, yellow

e 2 each, 1 x 3 plate, yellow




li t is tan .ao,o, • • 1 each, 4 x 4 plate, yellow

0 4 each, 2 x 2 flat tile, yellow

1 I each, 2 x 2 angular plate, redC D 1 each, rubber band, black

LEGO Dada is the fi tt l ea tge ted i v i s i on of LEGO Systems06'0decta 9 6 2 2

Documents

Lego Levers