After introducing Circles with a center not at the origin, try using this pattern puzzle to start or end class with. Many of the problems have similar centers and radii which will assess if students understand the difference in transformations to the right, left, up and down, and also that the formula for circles is equal to r^2. Pattern Puzzles can be used as bellwork, a quick activity in class, something to end class with, or even used as review throughout the year. They are so versatile! I like having these activities on my students’ desks when they walk in. The students know to get started checking their homework and completing the puzzle. This activity is great practice for "Drag and Drops" with Common Core.
The Math Lab