Design based on Conic Sections. Students will learn how to modify a non-function equation to an equation of a function which can be used on a graphing calculator. They will visually see when the equations are written separately for the upper half and lower half of the circle.  
Students can create a design bases on their own set of equations. They can create any design of which equations can be written. Students prefer to create her or his own design rather than duplicating.