Subject : Science

Topic : Simple Machines - Lever

Level : Primary Six

Duration : 3 periods

• Pupils know how to use the courseware. Eg how to get back to the main menu, how to move from the revision portion to the activities portion etc.

• Pupils should be able to identify the load, fulcrum and effort in the three classes of levers used in daily lives.

• Pupils should be able to assess the advantages and disadvantages of the different types of levers based on the following criterias :

- the distance travelled by the force

1. Titles of Courseware : Tutor-On-Demand - P6 Science
2. A pair of scissors, nut-cracker, tweezer, tongs, spoon and tin
3. A wooden plank and a fulcrum
4. Teacher-prepared worksheets

• Classroom
• Computer Lab

1. Set up a 'see-saw' using the plank and the fulcrum.

1. place a load on one end of the 'see-saw'
2. elicit from pupils their experiences when playing on the see-saw
3. ask questions : - what do you think will happen when I place a load on the end

- In which direction did the effort move?

- What can we do if we want to use lesser effort to lift the load?

2) From the activity, introduce and define the terms 'load', 'effort' and 'fulcrum'.

3) Show pupils a pair of scissors and pupils to tell the class how it works. Pupils to

identify load, fulcrum and effort of the scissors.

4. Do likewise for the nutcracker, tweezers, tongs and broom.
5. Introduce the term first class lever, second class lever and third class lever to the pupils.
6. Divide the whiteboard into three columns with heading 'first-class lever', 'second-class lever' and 'third-class lever'. Pupils to match the objects discussed earlier to the different columns.
7. Based on the simple machine ('see-saw') set up, ask pupils to discuss how it helps to make our work easier.
8. Pupils to be aware of the direction moved by the load and effort, the distance moved by the load and effort and the effort needed to lift the load.

• Second Part ( 35 mins)

4. Bring the pupils to the computer lab. One pupil to one computer. Row leaders to collect the courseware - Tutor-on-Demand P6 from the teacher and give out to individual pupil.
5. Pupils to go to the revision module - 'lever' to revise and consolidate what they have learnt. They will be given 20 mins to do the activity.

11) After 20 mins, at the blow of the whistle, pupils are to stop their activity and go to

the 'Activity' section of the courseware to test their understanding on 'lever' learnt.

Pupils will be given 15 mins to complete the activity.

12. Row leaders to collect the CDs back from the pupils and teacher to check to make sure that all the CDs are collected.

• Third Part (25 mins)

12. Pupils to go back to class. Pupils to do worksheets prepared by the teacher.

Appendix 1

Name : ______________________ Marks : _________/20

Class : 6/_______ Date : ____________

Put the simple machines listed in the box below into the correct column.

Claw hammer tweezers wheel barrow

Broom bottle opener crow bar

Scissors fishing rod nut cracker

Lever

Section B

Fill in the blanks with the suitable answer.

1. In the third type of lever, ______________is between the ______________ and the ________________.
2. The first class lever makes work easier because it changes the ___________ of force.
3. In order to lift a load with lesser effort, the fulcrum must be put nearer to the ___________.
4. In a ______________ lever, the distance moved by the load is longer than the distance moved by the effort.

5)

In the diagram above,

1. fulcrum is at position _____________.
2. effort is applied at position ____________.
3. load is at position ____________.

6) How does the lever make our work easier?

7. How do you differentiate a first class lever from a second class lever?