Semi Detailed Lesson Plan
Mathematics 8
I.
Learning Objectives
A. Content Standard: the learners demonstrates understanding of key concepts of logic and
reasoning.
B. Performance Standard: the learners is able to communicate mathematical thinking with
coherence and clarity in formulating and analyzing arguments.
C. Learning Competency: the learners writes a proof (both direct and indirect). (M8GE-IIij-1)
D. Objectives: At the end of the session, the students will be able to:
 define direct proof and indirect proof,
 appreciate the importance of proving in real-life situation, and
 write direct proof and indirect proof.
II.
Content
A. Topic: Writing Proofs (Direct and Indirect)
B. Reference: Orlando A. Oronce, et. al , E-Math III pages 78- 88
Writing direct and indirect proof (https://youtu.be/RNZtQJJq98ot)
C. Materials: PowePoint Presentation, laptop, manilapaper, and chalk/marker.
D. Method: Outcome-based Education Learning
III.
Procedure
A. Preliminary Activities
 Prayer: The teacher will choose one student to lead the prayer.
 Greeting: The teacher will greet the students.
 Checking of Attendance: The monitor of the class will be requested to to check
the absent in the class
B. Motivation
The teacher will show several math riddles for the students to answer. The teacher will
introduce the new topic after the motivational activity.
C. Review
The teacher will ask the students about the topics that was discussed last meeting.
 What was the lesson all about last meeting?
 Do you have any questions about the lesson that was discussed last meeting?
D. Discussion Proper
 The teacher will discuss to the learners the different types of writing a proof.
 The teacher will use this discussion to emphasize the importance of clear and
concise language, logical reasoning, and a well-organized structure in writing
mathematical proofs.
 The teacher will provide the students with a mathematical statement and will ask
them to write a proof for it.
 The teacher will provide guidance and support as needed, but will encourage the
students to work independently and to use their critical thinking skills to construct
a clear and logical proof.
E. Developing Mastery
Group Activity
 The teacher will provide the students with several mathematical statements and
will ask them to work in pairs to write a proof for each one.
 The teacher will walk around the classroom to provide guidance and support as
needed, but will encourage the students to work independently and to use their
critical thinking skills to construct a clear and logical proof.
 The teacher will provide feedback on the students' work and will encourage them
to revise and improve their proofs as needed.
F. Generalization
The teacher will ask the students to sum up the lesson by applying what they have learned
in their daily lives.
IV.
Assessment
The teacher will present a PPT presentation that contains mathematical statement that the
students need to proof.
V. Assignmment
The teacher will ask the students to classify the steps in writing proof (both direct and
indirect) accordingly to the type of proof
Prepared by:
Poblacio, Paul Sebastien D.
BSEd-Mathematics II
Group Activity Direction & Rubric
Direction: The class will be divided into three groups. The teacher will give five mathematical
statements that each group needs to prove both direct and indirect proof. Each group only have 30
seconds to formulate the proofs. The teacher will grade the proofs of each group according to the
rubric and the group who will have the highest grade will receive a point. The group who gathered
the most points will be the winner.
Rubric for Group Activity
Performance Levels
Criteria
Correctness
Mathematical
Relevance
Proof Technique
Outstanding
Satisfactory
The steps in the
proof are complete
and correct
The steps in the
proof are mostly
correct but involves
few minor flaws.
Some of the
mathematical
statements and
computations are
irrelevant.
Selects the correct
proof technique but
then articulates
incorrect
assumptions
Mathematical
statements and
computations are
relevant.
Selects the correct
proof technique and
correctly articulates
associated
assumptions
Did not meet the
expectation
The steps in the
proof are complete
but most are
incorrect
Most of the
mathematical
statements and
computations are
irrelevant.
Selects an
inappropriate proof
technique