Course 1 Online!
Henrico County Public Schools, Virginia
Number and Number Sense

Computation and Estimation

Measurement and Geometry

Probability, Statistics, Patterns, Functions, and Algebra

SOL Review Materials
Focus: Problem Solving with Area, Perimeter, Volume, and Surface Area

The student will
a)   define π (pi) as the ratio of the circumference of a circle to its diameter;
b)   solve practical problems involving circumference and area of a circle, given the diameter or radius.  
Essential Knowledge and Skills
  • Derive an approximation for pi (3.14 or 22/7) by gathering data and comparing the circumference to the diameter of various circles, using concrete materials or computer models.
  • Find the circumference of a circle by substituting a value for the diameter or the radius into the formula C = pd or C = 2pr.
  • Find the area of a circle by using the formula A = π r^2.
Essential Understandings
  • What is the relationship between the circumference and diameter of a circle? The circumference of a circle is about 3 times the measure of the diameter.
Vertical Articulation
  1. SOL 4.7ab - a) estimate/measure length, describe result in metric/U.S. Cust units; b) ID equivmeasurements
    between units within the U.S. Cust system and between units within the metric system
  2. SOL 5.9 - identify/describe diameter/radius/chord/ circumference of circle
  3. SOL 8.11 - solve practical area/perimeter problems involving composite plane figures
Instructional Materials
  1. Enhanced Scope and Sequence Lesson: Going the Distance (PDF) - Applying formulas to measure attributes of shapes (Word)
  2. Notes: Perimeter, Circumference, and Area (flipchart) - 76 slides: notes, multiple choice, interactive practice
  3. Notes: Circles (flipchart) - 14 slides: notes, videos, interactive website and multiple choice questions to understand area and circumference of circles
  4. Notes: Circles (ppt) - powerpoint version of the above flipchart
  5. Activity: Area and Circumference Match (pdf) - 14  questions matching the questions to the answers.
  6. Activity: Measuring Circles (pdf) - fill in chart to learn how to find pi by measuring different circles
  7. Activity: Origami - Finding the Circumference of a Circle (pdf) - fortune teller activity to practice solving circumference
  8. Activity: Finding the Circumference of a Circle Game (pdf) - board game to practice finding circumference of circles
  9. Activity: Bubble Mania (pdf) - students make bubbles and fill in a chart finding the circumference
  10. Activity: Pi and Area Investigations (pdf) - fill in chart to help with vocabulary of circles, investigation to find and understand circumference and area of circles
  11. Song: Circle Song (flv) - sound file
  12. VDOE Algebra Readiness Curriculum Companion: Exploring Circles (pdf)
Real World Lessons
  1. Dan Meyer - Penny Circle - How many pennies will the big circle will hold?
  2. Dan Meyer - Coin Carpet - If you were going to carpet the room with a single kind of coin, which would be the cheapest option?
  3. Dan Meyer - Brita - How many times would all the water bottles used in the US in a year wrap around the world?
  4. Mathalicious: Pizza Pi - Pizza Hut pizzas come in three sizes: large, medium and personal. Which size is the best deal, and is it ever a good idea to buy the personal? 
  5. Mathalicious: As The World Turns - How fast is the world spinning, and is it the same everywhere?
  1. Worksheet: Area and Circumference Review (doc) - 14 practice problems finding area and circumference
  2. Worksheet: Circle Patterns (doc) - measure 7 circles (not provided) to understand the relationship and patterns between circumference and diameter
SOL Mini Quiz
  1. SOL 6.10ab Mini Quiz: Circumference and Area (pdf)
  1. Mathematics Assessment Project: A13: Historic Bicycle - Apprentice - In this task, you will figure out some problems about a strange old bicycle.
  1. Math Rap - Don't Let Pi Make Ya Cry! (mp4)
  2. Math Playground: Circumference
  3. PH: Finding circumference
Explore Learning
  1. Sadlier: Circumference :
  2. Quia: Circumference and Area of a Circle
  3. Learn Alberta: Select Shape and Space - Circles
  4. BrainGenie: Area and Circumference of Circle
  5. Illuminations: Circle Tool
VDOE Interventions
  1. VDOE Algebra Readiness Curriculum Companion: Exploring Circles - (SOL 6.10ab) The lessons focus on exploring the relationships among the radius, diameter, center, circumference, chord, and area of a circle and on using formulas involving pi. (pdf)
Common Core Standards