A detailed lesson plan all about circles and its related parts. It also tackles about calculating the area and circumference of a circle.

1. LA SALLE UNIVERSITY
Ozamiz City
Field Study 2: Observation and Teaching Assistantship
DETAILED LESSON PLAN IN MATHEMATICS 7
Content Standard: The learner demonstrate understanding of key concepts of geometry of shapes
and sizes, and geometric relationships.
Performance Standard: The learner is able to create models of plane figures and formulate and
solve accurately authentic problems involving sides and angles of a polygon.
Learning Competency: The learner illustrates a circle and the terms related to it. (M7GE-IIIh-i-
1)
I. Objectives:
At the end of the lesson, the students must have:
a. illustrated a circle and the terms related to it. (M7GE-IIIh-i-1)
b. calculated the Area and circumference of a circle.
c. discussed the importance of choosing circle of friends.
II. Subject Matter: Circles
a. Reference: Luna, C. (2017). Circles and Its Parts. Retrieved from
https://www.slideshare.net/iamcarloluna/circle-and-its-part-math-7-3rd-quarter-83629044
b. Materials: PowerPoint presentation, Wordwall, Polleverywhere, youtube,
III. Procedure: 5A’s Method
Teacher’s Activity Students’ Activity
Preliminaries
Good morning, Class! Before we start, let us
first have a prayer.
How are you today, Class?
Very good! For me to check your attendance
this morning, kindly choose one character that
“Let us all remember that we are in the most
holy presence of God… Amen”
We are good, Sir.

2. best describes your feeling today. Type your
answer in the message box.
Let me inform you of the basic rule in my
class which is RESPECT. I want all of you to
be respectful because if you respect then you
are worthy to be respected. Is that clear class?
Excellent!
A. Awareness
1. Review
The topic that you discussed last meeting was
about the concave and convex polygon.
For me to check if you already understood the
topic, let us have a short activity.
Directions: Give what is asked in each item.
1. What polygon has 5 sides?
a. Quadrilateral b. hexagon
c. pentagon d. heptagon
2. What closed plane figure formed when
fitting together segments end to end?
a. polygon b. Octagon
b. Nonagon d. dodecagon
3. What type of polygon don’t have diagonal
in the exterior of the polygon?
a. concave b. convex
b. equilateral d. equiangular
4. What type of polygon have at least one
diagonal is in the exterior of the polygon?
a. concave b. convex
b. equilateral d. equiangular
(Students do as told)
Yes, Sir.
Expected Answers:
1. C
2. A
3. B
4. A
5. A

3. 5. What do you call a polygon that is both
equilateral and equiangular?
a. Regular polygon b. Irregular polygon
b. Normal polygon c. Equal polygon
2. Motivation
Class! Before we proceed, I want you to sing
with me.
Are you ready, class?
Okay! Turn on your microphone and sing
with me.
Link:
https://www.youtube.com/watch?v=zj6YKO
CrS74
Do you like the song, class?
What is the song all about, class?
That is right!
3. Statement of the aim
To know more about circles and its parts, I
want you to be with me this morning as we
will discuss circles. I want you to listen
carefully because at the end of the lesson you
are expected to attain the following
objectives:
a. illustrated a circle and the terms related to
it. (M7GE-IIIh-i-1)
b. calculate the Area and circumference of a
circle.
c. discuss the importance of choosing circle of
friends.
Yes, Sir.
Yes, sir.
The song is all about the circle and its parts.
Yes, Sir.

4. Are the objectives clear to you, class?
B. Activity
Activity 1:
Now, let us have our first activity titled
“Name Me”. Based from the song earlier, I
want you to name the parts of a circle.
Directions: Determine the parts of the circle
illustrated in the picture.
1.
2.
3.
4.
5.
6.
C. Analysis
Let us check if you name the parts of the
circle correctly.
Expected answer:
1. Radius
2. Diameter
3. Chord
4. Secant
5. Tangent
6. Circumference
A circle is a perfectly round shape.

5. But before going to the parts of the circle,
does anyone here who has an idea of what a
circle is?
Very good! That is one of the definitions of a
circle.
In other words, a circle is the set of all points
in a plane that are the same distance form a
fixed point called the center.
I have here a circle, what do you see inside
the circle?
Okay! There is a point at the center of the
circle, this point is called the center or the
central point. Circles are named through their
central point. So, what is the name of this
circle?
Excellent! The name of this circle is circle a
because the center or the central points is A.
Is it clear, class?
Alright! Based from your answer in our
activity, what is the parts of a circle that is
illustrated in this picture?
Correct! Based on the picture, what do you
think is a radius?
I can see a point located at the center of the
circle.
The name of the circle is Circle A, Sir.
Yes, Sir.
It is a radius, Sir.
A radius is a line segment joining the center
and a point on the circle.

6. Brilliant! A radius is a line segment joining
the center and a point on the circle.
If we write B on the other end of the radius
then we have now segment AB as the radius
of circle A.
All radii in a circle have equal length. Radii is
the plural form for radius.
Is it clear, class?
Magnificent! Now let us proceed.
Based from your answer in our activity, what
is the parts of the circle that is illustrated in
this picture?
Excellent! Based from the illustration, what
do you think is the definition of a diameter?
Brilliant! A diameter divides the circle into
two equal parts. Also, the measurement of the
diameter is twice the measurement of the
radius and the central point is the midpoint of
the diameter.
If we write C and D at the endpoints of the
diameter then we have segment CD as the
diameter of a Circle A.
Yes, Sir.
It is the diameter, Sir.
Diameter is a line segment that passes the
center of the circle.
A B
C D
A

7. Let us say, the radius of the circle A is 4 cm,
how long is the diameter of the circle A?
Very good! What if the diameter of the circle
A is 16 cm, how long is the radius?
Brilliant! Is diameter already clear, class?
Good! Let us now proceed.
Based from your answer in our activity, what
is the parts of a circle that is illustrated in this
picture?
Based on the illustration, what do you think is
the definition of a chord?
Correct! A chord is a line segment whose
endpoints are on a circle.
We have segment HF as an example of a
chord. So, now I have a question, are all
diameters considered as a chords and are all
chords considered as diameters?
Excellent! All diameters are considered as
chords but not all chords are considered as
diameters because not all chords passes
through the center of the circle.
Is it clear, class?
Okay! Let us now proceed.
The diameter of the circle A is 8 cm.
The radius is 8 cm, Sir.
Yes, Sir.
It is the chord, Sir.
A chord is a line segment whose endpoints
are on a circle.
Apparently, all diameters are considered as
chords but not all chords are considered as
diameters because not all chords passes
through the center of the circle.
Yes, Sir.
H
F

8. Based from you answer in our activity, what
is the parts of a circle that is illustrated in this
picture?
Based from the illustration, what do you think
is the definition of a secant?
Exactly! A secant is any line, ray, or segment
that contains a chord. It is a line that intersects
a circle in two points.
What do you think is the segment of the
secant in this illustration?
Alright! Let us proceed.
Based from your answer in the activity, what
is the parts of a circle that is illustrated in this
picture?
Magnificent! What do you think is the
definition of a tangent based from this
illustration?
Exactly! A tangent is a line that intersects a
circle at exactly one point.
If we write L and M at the endpoints of the
tangent, then our tangent will be the segment
LM.
It is a secant, Sir.
A secant is any line, ray, or segment that
contains a chord. It is a line that intersects a
circle in two points.
The name of the secant is the segment JK.
It is a tangent, Sir.
A tangent is a line that intersects a circle at
exactly one point.
J
K

9. Is it clear, class?
Okay! Let us proceed.
What is the part of the circle that is illustrated
in this picture?
Very good! It is the circumference.
How can you define circumference based
from the illustration?
Excellent! Circumference is the distance
around the circle. It is like the perimeter of
other shapes such as squares, rectangles, and
the likes.
Is it clear, class?
Very good! This is the formula to calculate
the circumference of a circle, class.
Circumference= πd
Where π is equal to 3.14
And d is the diameter of the circle.
Let us have this for example.
The diameter of our circle is 6 cm, what do
you think is the circumference of our circle?
That is correct! How did you get it?
Very good! We can get the circumference by
multiplying the diameter to 3.14.
Yes, Sir.
It is the circumference, Sir.
Circumference is the distance around the
circle.
Yes, Sir.
The circumference of the circle is 18.84 cm,
Sir.
By multiplying 6 to 3.14.
6cm

10. Let us have this another example.
The radius of a circle is 4cm, what do you
think is our circumference?
Brilliant! How did you get it?
Excellent! Since radius is half the diameter,
we will simply multiply the radius by 2 and
multiply the answer to 3.14.
Is it clear, class?
Very good! You might wondering class,
where is 3.14 came from?
3.14 or the pi class is circumference divided
by the diameter.
Circumference of the circle divided by its
diameter is always equal to 3.14.
Is it clear, class?
Now let us proceed.
This is the formula to solve for the area inside
the circle, class.
𝐴 = 𝜋𝑟2
Where 𝜋 is equal to 3.14 and r is the radius.
Let us have this for example.
The circumference is 25.12, Sir.
Since radius is half the diameter, I multiply 4
by 2 and multiplied it to 3.14.
Yes, Sir.
Yes, Sir.
4cm
4cm

11. What do you think is the area of this circle?
Wow! How did you get it?
Very good!
𝐴 = 𝜋𝑟2
𝐴 = 3.14 𝑥 42
𝐴 = 50.24𝑐𝑚
Do you understand, class?
Do you have any question about circles and
its parts?
Good!
D. Abstraction
Can you give me three parts of a circle?
Correct! Give me another three parts of a
circle.
Excellent!
Now! Who can cite any experiences on how
circles are used in our daily lives?
Very good! Circle is used in our daily lives
like the different things that we used in our
home like clocks, circular plates, circular
table, and many more.
E. Application
The area of the circle is 50.24cm, Sir.
𝐴 = 𝜋𝑟2
𝐴 = 3.14 𝑥 42
𝐴 = 50.24𝑐𝑚
Yes, Sir.
None, Sir.
Parts of a circle are Radius, Diameter, and
chord.
Parts of a circle are Secant, Tangent, and
Circumference.
Circle is used in our daily lives like the
different things that we used in our home like
clocks, circular plates, circular table, and
many more.

12. For me to check if you really understood the
topic today, let us have our 2nd activity.
Activity 2: “Know Me Please”
Directions:
Give what is asked in the problem.
Is the activity clear, class?
1. An electronic and communication engineer
designed a circular disk to be put up in a call
center building. Before he installs the disk, he
asked his workers to check the disk and its
parts. What are now the parts of a disk?
Identify the radius, chord, diameter, secant,
and tangent of the disk below.
LINK:
Good! You can now start answering.
Value Integration
Our discussion this morning class tackles
about circle.
In relation to our real life, we have circle of
people that influenced our characteristics.
Yes, Sir.
A
D
F
H
I
G
E
C
B

13. Now, why is it important to choose the circle
of people that will surround us, class?
Correct! What else?
Alright!
Class, you should form a circle of people that
will support you to your dreams, comfort you
when you feel sorrow, lend hand when you
need it, and accept you for who you are.
Is that clear, class?
Very good!
We should choose the circle of people that
will surround us so that we will not be
influenced to do bad things.
We should choose the circle of people that
will surround us so that we will not be
harmed.
Yes, Sir.
IV. Evaluation
Directions: Give what is asked in the problem.
1. What is the distance around the circle?
a. Area b. Diameter
c. Circumference d. Radius
2. Which part of a circle is a line segment that goes from one end of a circle to the other end of a circle
and passes through the center?
a. Radius b. Circumference
b. Secant d. Diameter
3. Circle A has a 24 cm radius. How long is the diameter?
a. 12 cm b. 48 cm
c. 150.72 cm d. 1, 808.64 cm
4. What part of a circle intersects circle at two points?
a. Tangent b. chord

14. c. diameter d. Secant
5. What part of a circle intersects circle at exactly one point?
a. Tangent b. chord
c. diameter d. Secant