This lesson plan is for a 9th grade mathematics class in Surabaya, Indonesia. Over two class meetings, students will learn about the surface areas and volumes of cylinders, cones, and spheres. In the first meeting, students will work in groups on a worksheet solving problems related to surface areas. They will then discuss their work and solutions. In the second meeting, students will work on a similar worksheet involving volume problems for cylinders, cones, and spheres. The goal is for students to correctly solve surface area and volume problems by the end of the two lessons.

1. LESSON PLAN
School : SMP Negeri 3 Surabaya
Subject : Mathematics
Grade/Semester : IX/1
Time : 4 x 40 minutes (2 meetings)
A. Standard Competency
2. Understanding the properties of cylinder, cone and sphere and determining
its size
B. Basic Competency
2.3 Solving the problems that are related to cylinder, cone, and sphere
C. Indicator
1. Solve the problems related to surface area of cylinder, cone and sphere
2. Solve the problems related to volume of cylinder, cone and sphere
D. Learning Objective
First meeting
1. Given some problems related to surface area of cylinder, cone and sphere,
the students are able to solve the problems correctly.
Second meeting
2. Given some problems related to volume of cylinder, cone, and sphere, the
students are able to solve the problems correctly.
E. Material
First meeting
The surface area of cylinder, cone, and sphere
Second meeting
The volume of cylinder, cone, and sphere
F. Learning Model
First meeting
Discussion learning
Second meeting
Discussion learning

2. G.Learning Activity
First meeting
Introduction (± 5 minutes)
(Phase 1: Clarify aims and establish sets)
1. Teacher generally presents the learning objective that is solving problems
related to the surface area of cylinder, cone, and sphere.
2. Apperception: Leads the students to recall the material that had been
learned before and correspond with the material that will be discussed such
as the formula of surface area of cylinder, cone and sphere.
3. Motivation: Motivates the students by relating the material that being
discussed with real life situation.
(Phase 2: Focus on discussion)
4. Teacher explains to students that in this meeting we are going to discuss
about how to solve problems related to surface area of cylinder, cone and
sphere.
5. Teacher divides the class into 5 heterogenic groups.
6. Teacher gives a worksheet to each group and asks them to do the
worksheet.
(Phase 3: Hold the discussion)
7. Teacher asks students to discuss with their groups.
8. Teacher asks some students to show their work and asks the others to give
opinion, comment or suggestion.
(Phase 4: End the discussion)
9. By recitation, students are followed in making a decision about this learning
or from the discussion.
(Phase 5: Debrief the discussion)
10. The students asked to review their discussion process, using some
questions below;
a. What is your opinion about the discussion today?

3. b. Do you give any chances to your friends to participate in discussion
process?
c. Do you appreciate to others opinion whether it’s different or no?