Inquiry Lesson Plan

Geometry CP
Grade Level: 10 th grade Subject: Similarity Unit: 8.3
Brittany Gunn
Title/Topic This lesson will be about determining what makes two figures similar.
Standards EA-3.8: Apply proportional reasoning to solve problems.
G-4.6: Apply congruence and similarity relationships among shapes (including quadrilaterals and
polygons) to solve problems.
Objectives (in terms of learning outcomes) 1. Students should be able to use their knowledge of proportions to solve problems.
2. Students will develop understanding of what it means for to figures to be similar, and should
be able to use that knowledge to solve problems.
Context This lesson and these objectives relate to my goals for this unit because students will be able to
determine what it means for two figures to be similar and how to create similar figures. This will
help students prepare for their upcoming HSAP exam. This lesson will also help students develop
critical thinking skills and reasoning to solving word problems. The lesson also involves a real-life
application to help engage students and show them how this concept can be applied. This is an
inquiry lesson because it integrates one of the essential features of classroom inquiry. The feature it
meets is that the “learner formulates explanations from evidence” in which the students are guided
in the process of finding this evidence, but they must do the work to see what the connections really
are. At the end of the lesson, students must create a definition for similarity, formulating an
explanation after seeing all of the evidence together.
Materials -Geometer’s Sketchpad (installed on all computers)
-One computer per every two students (students are paired up before lesson)
-Similar Polygons worksheet for each student (attached)
-Projector & SmartBoard (for teacher to use and keep students on the correct track)
Assessment Students will be assessed through the lesson at the different stopping points, when the instructor will
check that all students are on the correct track. Students will also be assessed informally through
their homework problems and formally during the next class when they take a quiz on similar
figures.
References Key Curriculum Press. (2002). The Geometer’s Sketchpad: A Dynamic Geometry Software
(Version 4.0) [Software]. Available from www.dynamicgeometry.com
Bennett, D. (2002). Exploring geometry with the geometer’s sketchpad. California: Key Curriculum
Press.

Time Part of Lesson Details & Specifics
As students walk in, their warm up will be on the board.
20 minutes
60 Minutes
Anticipatory Set (Focus, Review,
Motivation)
Activities
&
Practice
Brittany Gunn
Good Morning Everyone! You’re warm-up is on the board. You should be
working on it as I go around and check homework.
Instructor will go around and check homework while students work on the
warm-up. When completed, Instructor will go over the warm-up problem
with the help of students guiding process. The homework solutions will then
be placed on the board for students to check their homework answers. The
instructor will go over homework problems.
If there are no more homework questions, then it is time for the quiz! Clear
your desks! You will have ten minutes to work on this quiz.
Alright everyone! Now that we have talked about ratios and proportions, we
can talk about similarity! To investigate similarity, we are going to be
working with Geometer’s sketchpad today! We are going to partner up and
each pair will be given one computer. Your partner has already been picked
for you. One student will be on the computer and the other student will need
to be writing down the information on the worksheets I am passing out. This
is most of the notes for today, so you need to make sure to stay on task.
Follow all directions on the sheet. You will see stopping points on the
worksheet. At these points you need raise your hand to let me know that you
have gotten to this point. That is when we will come together to talk about
what you have learned so far. Any questions right now? I am going to pass
out a computer to the pairs and you can get started.
Instructor will pass out the directions and read the target question for the
day. Then the instructor will pass out computers to pairs and walk around to
monitor student work. Instructor will already have stages completed and on
the SmartBoard to show the class where they should be at particular
stopping points.
1 st Stop – Students will look to board and instructor will show students what

10 minutes
Closure (Assessment)
Brittany Gunn
they should have at that time as well. They will discuss that there should be
two figures and that they have just created similar polygons. But we have to
find out the properties to understand what it means to be similar. When you
move the center, what happens? Next you are going to be measuring the
angles. I’m going to show you an example of how to do this.
2 nd Stop – Make sure to answer the question and move on to the next
directions. You’ll be measuring sides next. SWITCH positions with your
partner.
3 rd Stop – Let’s talk about what we’ve seen about sides and angles so far.
What do you notice about the angles in the two figures? Anything about the
sides? For the next portion, you need to use what we learned at the
beginning of this unit about corresponding sides. Then you’ll be finding
ratios.
4 th Stop – Let’s talk about what we have seen overall. What did you notice
about the ratios? What happened when you dragged one point of your
figures? So what does it mean to be similar? Together we will use what we
have learned about similar polygons to answer the question at the beginning
of the worksheet.
Class will work together to answer the question. Then instructor will debrief
students and switch over to a notebook page to work through more
examples and the one theorem from this section. For these examples
students will solve individually, utilizing think-pair-share and students
coming to the board to solve problems.
Your homework assignment is on the board. Problems similar to what we
have done are on your homework.
Review of what we have learned today. Talk about Geometer’s sketchpad
and ask students what they think of it and how it helped them or did not help
them understand similar polygons.