LESSON PLANLevel : Junior High SchoolSubject : MathematicsClass : IXSemester : ITopic : Similarity and CongruenceStandard Competence : Understanding the similarity offigures and the use of it inproblem solvingTime Allocation : 2 x 40 minutesStandard CompetenceUnderstanding the similarity of figures and the use of it in problem solvingBasic CompetenceIdentifying similar and congruent figuresIndicators1. Cognitivea. Determining whether or not two figures are similarb. Mentioning the pairs of similar figuresc. Solving problems dealing with similar figures2. Psychomotora. Drawing two similar figuresb. Drawing two figures which are not similar
3. Affectivea. Characterized BehaviorsResponsibility, willingness to help others, and the feel of neversurrender.b. Social SkillsTeam working, be active in discussion, be brave to deliver ideas, beopen to criticisms, and be able to give others the opportunity to speakup.Learning Objectives1. Cognitivea. Given two figures, students are supposed to be able to determinewhether or not the figures are similarb. Given some problems dealing with the concept of similarity, studentsare supposed to be able to solve them.2. Psychomotora. After learning about similar figures, students are supposed to be ableto draw a pair of similar figures.b. After learning about similar figure, students are supposed to be able todraw a pair of figures which are not similar.3. Affectivea. Characterized BehaviorsBeing involved in a student-centered learning activities, students aresupposed to be able to show responsibility, wilingness to help others,and the feel of never surrender at least be judged as “Starts to appear”.b. Social SkillsBeing involved in a student-centered learning activities, students aresupposed to be able to work in teams, be active in discussion, be open
to criticisms, and be able to give others the opportunity to speak up atleast be judged as “In Progress”.Learning ModelLearning Model : Problem-Based InstructionLearning Activities Introduction (± 10 minutes)1. Phase 1.Students on the issue orientationo Teacher leads the students to recall what they have learned fromthe previous meeting. These questions may help: “What did youlearn in the last meeting? Is it about similarity? What are theproperties of two similar figures? When are two figures said to besimilar?”o Motivation: Teacher gives an illustration of an event taken fromdaily life related to the concept of similarity. Here is one of thepossible illustrations.All of you must have allowance orpocket money. Your parents mostlikely give you the money at thebeginning of the week. Now, take alook at the money that you have inyour pocket right now! Do you haveany coins with you? Last meetingwe had studied about similarity andthe properties of two similar figures. Now, what do you think about the coins? Arethey similar? Why are they or why are not they? And now, do you have cash? Inwhat shape are they? Are they similar? Why are they or why are not they?o Teacher communicates the outlines of basic competence andindicator that will be learnt.
o Teacher leads students to recall the lesson that had been learnt inthe previous meeting e.g. “when are two figures said to be similar?What are the requirements for two figures to be congruent?”.o Teacher may „gradually‟ lead students to deal with the topic whichis going to be delivered in the meeting. Main Activities (± 70 minutes)2. Phase 2.Organize students to learno In this stage, teacher can divide students into several learninggroups containing three to four students.o Further, teacher can pose a problem dealing with similarity (theproblems are available in the worksheet).3. Phase 3.Guide theinvestigationof individualand groupo Teacher guides and assists students to work in groups to solve theproblems.4. Phase 4.Develop and present the worko Teacher helps students to present the work (the result of thediscussion) in front of the class.5. Phase 5.Analyze and evaluate the problem solving processo In this phase, teacher may ask several groups to present their work.o Teacher emphasizes that the other student who do not get thechance to present their work shoul give their opinion regarding tothe presenting teams‟ works. Here, teacher leads the discussion andhelps students to settle the problem by getting closer to the rightanswer.Note: Teacher can also modify the learning activities by posing more than oneproblem. In modifying this, teacher may provide more than one worksheet. Then,the learning activities will be going back to the second step until the fifth step.This can be repeated until all the problems have been settled. Here, I suggest touse two or three problems in two or three worksheets. Closure (± 10 minutes)o Teacher leads students to conclude what they have learned that day.
o Teacher might ask the students to write a reflection regarding to thelesson and the learning activities that they have experienced thatday.o Teacher may also gives homework for students to practice.o Teacher closes the lesson that day.AssessmentThe assessment can be done by assessing the student performance during theproject presentation, the content of the work presented, and also the activitieswithin the groups. The students who do not present their work are assessed by theworksheet/s that have/s been completed.