Course: 7 Grade Math DETAIL LESSON PLAN (Obj. 4b) Lesson 8 .

Course: 7th Grade MathStudent Objective(Obj. 4b)TSW find the circumference and area of circles.DETAIL LESSON PLANWednesday, February 8 / Thursday, February 9Lesson8-5Textbook Pages: 394-397HomeworkPerimeter / Area Half Sheet (5 problems)Last Night’s HomeworkArea Worksheet (Berg created, 8 problems)BellworkGet green quick notes and calculator. Work perimeter/area study guide problem #’s 1, 2, 5, 6, 7, 8Prior Knowledge Review answers to the bellwork. Review last night’s homework. Earlier in the week, we learned how to find the Perimeter of the different kinds of shapes.The perimeter is the distance around a figure. We also, learned how to calculate the Area of different shapes: Parallelograms, Trapezoids and Triangles! Does anyone remember a Real Life situation where you would use or see “perimeter” or “area”? Wait for student response.Hint . I showed you a PowerPoint called “Areas of Disaster”. Does that ring a bell?Students will say . Tornado disaster area,Rope off an area of a crime scene,Oil spill, Hurricane Katrina .Anticipatory Set Now, there is one more shape we need to talk about Circles! Play X-Files audio. Show “Crop Circles” PowerPoint. Crop Circles Are they Real or a Hoax?Teacher Input Pass out student notes. Pass out green quick notes (area formula sheets). Define radius, diameter, and pi.Explain how to find the circumference of a circle using a formula.Have students work two you-try problems (independently).Explain how to find the area of a circle using a formula.Have students work two you-try problems (independently). Classwork:Extra Practice:C A “Crop Circle Math”. (Kagan RallyRobin)TSW find the circumference and area of a real life crop circle.FSP Pages 36, 44 (circled only)Students may begin their study guide for test.AssessmentObservation and questioning. Major text next class.Closure1) What formula do you use to find the circumference of a circle? C d2) How do you find the circumference of a circle if they give you a radius instead of the diameter?First find the diameter: 2 x r, then C d3) What formula do you use to find the area of a circle?A 4) How do find the area of a circle if you are given the diameter instead of the radius?First find the radius: r d, then A

Student Notes8-5 CirclesTextbook Pages 394 – 397New VocabularyRadius – Is the distance from the center of the circle to the outer edge.Diameter – Is the distance from one side of the circle to the other.Pi – Is a number used when working with circles. (Also known as 3.14)The symbol for pi is.Finding the CircumferenceThe distance around a circle is call it’s Circumference (C).Pi is a number used when working with circles. Also know as14 m7mDiameter (d) 3.14.Radius (r)Find the diameter:d 7 2 14C C C 3.14 x 14C 3.14 x 14Finding the AreaThe Area (A) is the amount of space inside a circle.8mRadius (r)16 mDiameter (d)Find the radius:r 16A A A 3.14 xA 3.14 x2 8

Crop Circle Math!Top circle:Bottom circle:Left circleRight circleCenter diameterdiameterCircumference is the distance around a circle. Find the circumference of each circle below.C dTop circleC ftBottom circleC ftLeft circleC ftRight circleC ftCenter circleC ftArea is the amount of space inside the circle. Find the area of each circle below.A Top circler A Bottom circler A Left circler A Right circler A Center circler A

Answer KeyCrop Circle Math!Top circle:Bottom circle:Left circleRight circleCenter diameterdiameterCircumference is the distance around a circle. Find the circumference of each circle below.C dTop circleC 47.1 ft3.14 x 15Bottom circleC 53.38 ft3.14 x 17Left circleC 50.24 ft3.14 x 16Right circleC 43.96 ft3.14 x 14Center circleC 200.96 ft3.14 x 64Area is the amount of space inside the circle. Find the area of each circle below.A Top circler 7.5A 176.6253.14 xBottom circler 8.5A 226.8653.14 xLeft circler 8A 200.963.14 xRight circler 7A 153.863.14 xCenter circler 32A 3,215.363.14 x

Perimeter / Area1) What is the perimeter of the followingregular hexagon?2) What is the perimeter & area of this shape?13 inP P 33 in23 in6 in12 inA 13 in3) James is building a circular deck that is 10 ft. in diameter. What is the area of the deck.4) Jimmy races around a track that is 100 m in diameter.What is the distance he travels in 1 rotation around the track? mBe careful! Does the word around pertain to area or circumference?5) Find the area of the shaded region of this irregular figure. 3 ftHint: Find the area of the triangle:A Subtract the area of the rectangle: A 9 ft6.5 ftArea of the shaded region 14 ftPerimeter / Area1) What is the perimeter of the followingregular hexagon?2) What is the perimeter & area of this shape?13 inP P 33 in23 in6 in12 inA 13 in3) James is building a circular deck that is 10 ft. in diameter. What is the area of the deck.4) Jimmy races around a track that is 100 m in diameter.What is the distance he travels in 1 rotation around the track? mBe careful! Does the word around pertain to area or circumference?5) Find the area of the shaded region of this irregular figure. 3 ftHint: Find the area of the triangle:A Subtract the area of the rectangle: A Area of the shaded region 9 ft6.5 ft14 ft

Area FormulasCirclesParallelogramA b hCircumferenceC RhombusA b hAreaA RectangleA b hSquareA b hTriangleA TrapezoidA b hArea FormulasCirclesParallelogramA b hCircumferenceC RhombusA b hAreaA RectangleA b hSquareA b hTriangleA TrapezoidA b h

Answer KeyPerimeter / Area1) What is the perimeter of the followingregular hexagon?2) What is the perimeter & area of this shape?13 in36P 33 in23 in6 inP 8212 in336A 13 in3) James is building a circular deck that is 10 feet in diameter.What is the area of the deck.78.54) Jimmy races around a track that is 100 m in diameter.314What is the distance he travels in 1 rotation around the track?mBe careful! Does the word around pertain to area or circumference?5) Find the area of the shaded region of this irregular figure. 3 ftHint: Find the area of the triangle:9 ftA 636.5 ftSubtract the area of the rectangle: A 19.514 ftArea of the shaded region 43.5

Course: 7th Grade Math DETAIL LESSON PLAN Wednesday, February 8 / Thursday, February 9 Student Objective (Obj. 4b) TSW find the circumference and area of circles. Lesson 8-5 Textbook Pages: 394-397 Homework Perimeter / Area Half Sheet (5 problems)