I like to have my students "discover" the equation of a circle, as opposed to simply giving them the formula and having them work with it.
I have them start with applying the Pythagorean Theorem to a right triangle with its hypotenuse spanning from the center of a circle to a point on the circle. After the kids have worked out the lengths of the legs, I have them work backwards to come up with the familiar form (x - h)^2 + (y - k)^2 = r^2.
I use this activity within cooperative groups, and I circulate to make sure they are getting the purpose of the questions.
The file includes spiral review problems.
This worksheet is intended to be written on directly.
Please download the pdf preview file first, so you can see exactly what's included; the product file is a word document, which you may personalize for your students.
Immediately before this worksheet, I use the worksheet named 'Transformations of Quadratic Functions for Geometry Spring 2014' (http://www.teacherspayteachers.com/Product/Transformations-of-Quadratic-Functions-for-Geometry-Spring-2014-1269868
), and immediately after this worksheet, I use the assessment named 'Geometry Group Practice Test Circles Spring 2014' (http://www.teacherspayteachers.com/Product/Geometry-Group-Practice-Test-Circles-Spring-2014-1269882