On 3-14-15 the Golden team celebrated Pi Day  by exploring the relationship between a circle's circumference and diameter. We measured spring-themed objects such as a frisbee, basketball, and party plates. Students used problem-solving skills as they worked in small groups to measure their round objects. They discovered the ratio of circumference to diameter is approximately 3.14...Pi! The more precisely they measured, the closer the ratio was to Pi. This lesson addressed common core standards in the 7th grade geometry strand. Students also engaged in a variety of mathematical practices including attending to precision, use of tools, and constructing arguments.