This is a set of 24 task cards designed to give kids practice calculating the circumference of a circle using 3.14/pi. The picture of each circle is shown, with either the diameter or the radius labeled.

These cards were designed for above level fifth graders who are just learning how to find the circumference of a circle. I made the cards primarily to give kids practice paying attention to whether they are given the radius or the diameter, before they calculate the circumference. (In each set of answers, I have intentionally included the answer kids would get if they forget to double the radius.)

I usually make multiple copies of the task cards and have students work with a partner to solve the problems, while I work with another group of kids. An answer key that is suitable for kids to use is included.

These cards support common core 7.G.4 (using formulas to work with circumference of circles).

This is an 8-page PDF file which includes 6 pages of task cards (4 per page for 6 pages), a 1-page recording sheet and a 1 page answer key.