The document describes a lesson on teaching 8th grade students how to calculate the surface area of a cube. It includes: 1) An introduction where the teacher reviews rectangular prisms and squares to build on previous knowledge. 2) A presentation where students examine cube models and determine all sides are equal, defining it as a cube. 3) An activity where students use the surface area formula for a rectangular prism to derive the formula for a cube: Surface Area = 6a2, where a is the length of one side. 4) Practice problems are assigned to reinforce calculating the surface area of cubes using the formula.

1. LESSON TRANSCRIPT
Name of the Teacher : SUPRIYA.M Standard : VIII
Name of the School : M.C.H.S.S Kumarapuram Division :
Subject : Mathematics Strength :
Unit : Prism Duration : 45’
Topic : Surface area of cube Date : 16.07.2014
CURRICULAR STATEMENT
The Students get an opportunity to attain and apply the following ideas.
i) To understand the term cube.
ii) To find the surface area of the cube.
CONTENT ANALYSIS
Terms : Cube, Surface area, length
Fact : The sides of a cube having same length
Concept : Finding the surface area of a cube.
Process : The surface area of the cube is six times the square of the side length.
Formula : Surface area of the cube = 6a2.
a - Length of one side of the cube.
Learning Outcome :
Remembering : The student will be able to recall about surface are of a rectangular prism,
volume of the cube.
The student will be able to recognize about surface are of a rectangular
prism, volume of the cube

2. Understanding : The student will be able to explain ideas about cube, surface area of cube
The student will be able to interpreting surface area of cube
Applying : The student will be able to using information in solving problems
The student will be able to implementing about surface area of cube
Analysing : The student will be able to breaking information into parts to explore
surface area of cube
Evaluating : The student will be able to justifying decision about surface area of cube
Creating : The student will be able to generating new ideas about cube and surface
area of cube
Interest : The students will be able to develop interest to identifying the models of
rectangular prism, square, cube
Skill : The student will be able develop skill in solving problems of surface area
of cube
Pre – requisties : Area of square, Surface area of rectangular prism.
Teaching learning resources : Model of square prism, model of a cube, chart
containing the formula surface area of the cube.

3. Class room Interaction Procedure Pupil’s response
Introduction:
To check the previous knowledge of the students,
teacher asks few questions.
Teacher shows the model of a rectangular prism
and asks what is the name of this geometrical shape
Rectangular Prism
What is the formula of find out the surface area of
rectangular prism ?
Surface area of rectangular prism = 2 (lb + bh + lh)
l – length of the prism
b – breath of the prism
h – height of the prism
Teacher shows the model of square and asks about
the geometrical shape.
Square
What is the formula to find out the area of square?
Area of square =
a – length of one side
2 (lb + bh + lh)
l – length of the prism
b – breath of the prism
h – height of the prism
Square
푎2

4. Class room Interaction Procedure Pupil’s response
Teacher then shows the model of cube
What is the name of this geometrical shape?
No response
Presentation :
Teacher divide the students into 4 groups and gave
the models of cube to each group.
Teachers asks the students to measures the length of sides
using scale and write it.
4cm 4cm
4cm
4cm
What is the speciality of this measure ?
All the sides are equal
If the sides are equal, then what is the name of the
geometrical shape?
Square
If the sides and it is a three dimensional shape, then
All the sides are equal
Square

5. Class room Interaction Procedure Pupil’s response
what is it?
Cube
So, with the help of the teacher, students came to a
conclusion that all the sides of the cube are equal.
Activity 2:
Teacher gives the activity card containing a
rectangular prism and asks them to write the formula for
finding the surface area of rectangular prism?
Then, teacher gave the model of cube to each
group, the cube which makes in the chart.
Teacher marks the length of one side of the cube as ‘a’
Then, teacher asks to find the surface area of cube,
by observing the model given.
a
a
a
To find the surface are of the cube, the length l,
breadth b, and height h all are of same length a,
Put this value ‘a’ in the formula of surface area of
rectangular prism and find out.
ie; Surface area of cube = 2 (a x a + a x a + a x a)
= 2(a2 + a2 + a2)
= 2 x 3a2
= 6a2
Cube
Surface are of rectangular
prism = 2(lb + bh + lh)
Surface are of rectangular
prism = 2(lb + bh + lh)
Surface area of cube
= 2 (a x a + a x a + a x a)
= 2(a2 + a2 + a2)
= 2 x 3a2

6. Class room Interaction Procedure Pupil’s response
What do you understand from this?
If ‘a’ is the length of one side of a cube, the surface
area of the cube is six times, the square of its length of one
side.
= 6a2
Generalisation :
If ‘a’ is the length of one side of a cube, the surface area of
the cube is six times, the square of its length of one side.
Teacher show a chart showing the surface area of cube.
Teacher asks the students to read the chart loudly.
Application :
Class Assignment:
1) If the length of one side of a cube is 10 cm. How
can we find the surface area of the cube?
What is the formula to find the surface area of
Students observes the chart
Students read the chart
loudly
Surface area of cube = 6a2
a
a
aA
aA a
Surface area of cube = 6a2
a – length of one side

7. Class room Interaction Procedure Pupil’s response
cube?
What is given?
How much?
 Surface area of the cube = 6a2
= 6 x 102 = 6 x 10x 10
= 600 cm2
Length of one side
Length of one side = 10 cm
Surface area of the cube =
6a2 = 6x 10x 10
= 600 cm2
Review:
What is the formula to find out the surface area of the cube ?
Home Assignment:
Length of one side of a cube is 15cm. What is the surface area of the cube?