Heather Stephan WESTERN MIDDLE, ELON, NC
7th Grade Math : Unit #7 - Geometric Figures : Lesson #11

Interior Angles of a Triangle

Objective: Students will apply their knowledge of angle relationships to set up and solve equations to find missing values in a triangle.
Standards: 7.G.B.5 MP1 MP2 MP3 MP4 MP6
Subject(s): Math
60 minutes
1 Launch - 10 minutes

OpenerAs students enter the room, they will immediately pick up and begin working on the opener – Instructional Strategy - Process for openers  This method of working and going over the opener lends itself to allow students to construct viable arguments and critique the reasoning of others, which is mathematical practice 3

Learning Target:  After completion of the opener, I will address the day’s learning targets to the students.  For today’s lesson, the intended target is “I can set up equations using angle relationships in order to solve for missing values."

2 Explore - 45 minutes

Guided Notes: This lesson will begin with very basic notes on the sum of the interior angles of a triangle.  Most students already know that the sum of the angles is 180, but I want to revisit that fact before moving forward with class.  I will ask for student input on what they think we should do if we know that the interior angles sum to 180, and we have angle measures and expressions for each angle.  I am hoping that they will be able to set up an equation based on what we did in the previous lesson. After working a couple of problems together, I will have the students work in their table groups to finish the practice and then go to the board to share their work.

Versatiles Activity: For the remainder of class students will work in their table groups to solve a mix of 12 problems that cover all angle relationships that we have studied.  I will use this time to pull a small group together for extra assistance as needed.

Versatiles Reflection
Student Self-Assessment

The versatiles activity is always a great way for my students to practice.  They like knowing right away whether they got the right answer or not, and they actually persevere more in solving the problems because they know the list of possible answers.  PLUS - I always tell them that I am human and make mistakes - so bonus points if you can find a mistake!  That is like a challenge for them :)  

Today this activity allowed me the time to catch some students up that had been out.  We have had a string of stomach viruses run through many of the students, so this activity allows me the time to sit and help those who need it.