LESSON PLAN

Education Level : Junior High School

Subject : Mathematics

Grade/Semester : VII/2

Time Alocation : 25 minutes

A. Standar Competence : Understanding relation between line and line, line

and angle, angle and angle, then determine the

size.

B. Basic Competence : Determining the relation between two line, size

and the types of angle

C. Indikator

1. Determining parallel, intersecting and skew lines

2. Identifying the properties of position two lines

D. Purpose Of the Lesson

1. Cognitive Purposes

a. Students can determine whether parallel, intersecting and skew lines.

b. Students can identify position of two lines.

2. Affective Purposes

a. To grow confidence to the students, namely when they present discuss

result and give an opinion when discuss in their group and when discuss

with teacher.

b. To plant individual responsibility, namely when the students doing the

quiz.

c. To plant social responsibility, namely when the students discuss in their

group they respect friends opinion, do task to group, can cooperate with

other friends.

d. The students appreciate to the teachers.

3. Psikomotor Purposes

a. Students can draw the line based on the position.

E. Material

1. Parallel lines

Two straight lines are parallel if :

a. They never meet or intersect

b. The perpendicular distance between the two lines is the same at all points on

the lines.

The symbol ‘//’ denotes ‘is parallel to’

Example :

A B

C D

AB // CD

2. Intersecting lines

Two straight lines intersect if they meet or cross each other at one point. The

point is called the point of intersection.

U

X Z

V

UV intercect XZ

3. Skew lines

Two lines are skew if they non coplanar lines and they do not intersect

Example :

H G

E

C

A B

Example of the pairs of skew lines is AB and FG

F

D

F. Learning Method

Model : Direct Instruction

Metode : Expository, discussion, ask and answer

Waktu : 25 minutes

G. Teaching and Learning Activity

Activity Time

Allocation

Introduction

1. Teacher make students ready to study, by asking the

condition of students (who is absent today?) (respect

to the friends aspect)

2. Teacher reminds about points, line segment, and line.

(the material is enclosure)

3. Teacher inform to the students about the material that

will be learn, namely about the position of two line.

4. Teacher shows the slides to the students that contain

pictures of railway, cross, and other picture that have

relation with position two lines. Then, teacher asks

How is the position of two iron bar on the railway?

How is the position of two wood on cross?

How is the position of the iron bar on the top of bridge

and iron bar on the railway?

Main Activity

1. Teacher ask 4 students to go in front of the class. Then

teacher give illustration about parallel line, by assume

that the position of the students are any points on the

line, then the line made from rope that hold by the

students.

4 minutes

2 minutes

2. Teacher explain about parallel line based on

illustration above.

3. Teacher shows a cube frame, then ask to the students

Can you show me, which one we call parallel line in

this cube frame? Is there intersection point of those

lines? Are those lines placed on same plane? So what

is parallel line?

4. Teacher shows the intersecting line on the first slide.

Then teacher asks to the students, can you find the

intersecting line in this cube frame? Teacher ask to the

students what is intersecting line. (Students can

identify the characteristic of intersecting line. If it is

difficult for students, the teacher will give question to

help)

5. Teacher shows skew lines using cube frame.

6. Teacher devides the class into two group, each group

is asked to do the activities in the worksheet

(Worksheet is enclosure).

7. Each group discuss about the task and must present the

discuss result.

8. Teacher gives explanation again about skew lines.

2 minutes

3 minutes

1 minutes

1 minutes

1 minutes

4 minutes

2 minutes

Closing

1. Guiding the students to summarize learning outcomes

by giving any question.

2. Teacher give individually quiz to evaluate the

knowledge of students about position of two lines.

(Quiz is enclosured)

2 minutes

3 minutes

H. Assesment

1. Assesment Technique : Tes and Non tes

2. Assesment Procedure :

No. Aspect that will be

evaluated Assesment Technique

1. Understanding concept.

( cognitive purposes)

Individual test

using quiz.

2. Confident, individual

responsibility, social

responsibility, teacher

appreciating (affective

purposes)

Observation (Non Tes)

by giving sign (V) on

likert scale assessment

sheet.

3. Ability to draw position of

two lines. (psikomotor

purposes)

Individual test using

quiz.

3. Assesment instrument : quiz, worksheet (enclosure)

I. Learning Source

1. Wintarti, Atik. 2008. Contextual Teaching and learning Matematika Sekolah

Menengah Pertama Kelas VII. Jakarta : Departemen Pendidikan Nasional

2. Worksheet

3. Media Pembelajaran : Material in Power Point

4. Mathematics aid : Cube frame, rope.

J. Enclosure

1. Material in Power Point

2. Apersepsi material

3. Worksheet

4. Quiz

5. Affective assesment sheet

6. Answer key and heading assesment.

Known Surakarta, 4 April 2012

Headmaster Teacher

............................. Augistri Putri P

NIP. NIM. K1309102

LIKERT SCALE OF AFFECTIVE ASSESMENT

NAME : ………………..

CLASS : ………………..

Give sign (V) on criteria that match with ability of students

No Question 1 2 3 4

1 Is student confidence when he/she present the discuss

result?

2 Does the student give opinion in their group when

he/she discusses?

3 Does the student give opinion when he/she discusses

in class with teacher?

4 Does the student do the quiz?

5 Does the student respect to friends’s opinion?

6 Does the student do group assignment?

7 Can student cooperate with others?

8 Does student appreciate to the teacher?

Note :

1 : less

2 : enough

3 : good

4 : very good

Final score =

STUDENTS WORKSHEET

Group : ………………….

Members : 1. ………………….

2. .…………………

3. …………………

Look The Picture bellow!!!

H G

G

G

C

A B

1. AB and FG are two skew edges. Find other 5 pairs of skew edges!

……………………………………………………………………….

……………………………………………………………………….

2. Is there any intersecting point on those pairs of skew edges?

……………………………………………………………………….

……………………………………………………………………….

3. Do the lines are parallel?

………………………………………………………………………

4. Are the pairs of skew edges placed on the same plane?

………………………………………………………………………

………………………………………………………………………

5. So, What is skew lines?

………………………………………………………………………

………………………………………………………………………

SKEW LINES

E F

D

ANSWER KEY OF WORKSHEET

1. The pairs of edges are :

AB and EH, GH and DA, DH and BC

DC and FG, GH and CB, DH and FG

DC and EH, AE and FG, BF and AD [15]

EF and AD, AE and BC, CG and AD

EF and BC, DH and BC, CG and EH

(Only choose 5 pairs)

2. No, there is not [10]

3. No, they are not [10]

4. The skew lines are lines that do not intersect and do not parallel. [25]

Value =

INDIVIDUAL QUIZ

Name : ………………..

Class : ………………..

1. Name all the pairs of parallel lines in the following figure!

B C

G

A D

F

Answer : ………………………………………………………………

……………………………………………………………….

………………………………………………………………..

2. Look at picture bellow!

U

V Z

W

Point X is intersection point between line …. and line ….

So, the position of those line is ….

X

3. Please draw a line that parallel to line bellow! (Hint : Use a ruler to find parallel

line)

S

T

How is the way you can find the parallel line?

Answer : …………………………………………………………….

……………………………………………………………..

……………………………………………………………..

4. Show one pairs of skew edges, besed on cube bellow!

A B

D

F

H G

Answer : ………………………………………………………………

………………………………………………………………

……………………………………………………………….

ANSWER KEY OF INDIVIDUAL QUIZ

1. AB // DC [10]

AE // FG [10]

BC // AD [10]

2. Point X is intersection point between line VZ and line UW [10]

So, the position of those line is intersecting lines [10]

3.

S

[15]

T

We can find it by using ruler. We place the ruler side on the line ST and we can

draw a parallel line based on another side of ruler, so the distance of two line

always same. [15]

4. The pairs of skew lines are AB and EH [10]

Value =

PERSEPTION MATERIAL

Teacher : Do you still remember about points?

Students : …………………………………….

Teacher : Do the points have size or shape?

Students :…………………………………….

Teacher : Do the points have a position?

Students : …………………………………….

Teacher : Please draw two points with different position!!

Now, draw a line through those two points!

Students : ……………………………………..

Teacher : If I have this line (teacher draw a line segment). What do you

think? What is the different?

Students : …………………………………….

Teacher : (teacher explain abaout line segment)

So, if I have cube frame (shows the cube frame), how many line

segment are there?

Students : ……………………………………..

Teacher : So, we can say there are 12 line in this cube because line segment

is a subset of line.