Lesson: Sum of Angles in Polygons
Lesson Objective
Lesson Plan
Element/Time 
Lesson Steps 

Do Now (8:30 – 8:40)/(10:00 –10:10) 
· T displays 4 review problems · S complete problems independently on do now sheet · T walks around to check hw/help students with do now questions · T/S review problems together · S correct their work to reflect the correct answers 

HW Check 
· T displays correct answers and work · S correct work with colored pencil T walks around to review specific students work · T/S review 3 questions 

Mini Lesson (8:50 – 9:25)/(10:20 – 10:55) 
· Review key idea from previous day – triangles equal 180° · Tell students that using just that information we can find the sum of angles in any polygon · T demonstrates using the triangle method to find the sum of angles in any polygon but splitting the polygon into triangles and then multiplying the number of triangles by 180. · T and S will practice first dividing polygons into triangles · S will practice working to find the sum of angles within different polygons. · T and S will conclude at the end of class that any quad will have 360, pentagon will have 

Skills Time (9:35 9:50) /(11:0511:25) 
· See if we can figure out a rule (using algebra) to find out the sum of angles in any polygon.
Sum = 180 (n – 2)
· Review week of angles · Read Sir Cumference and the Great Knight of Angleland · Make sure flip books are up to date

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