Pi Hoop–Deal or Dud?

After designing a lesson for students to discover pi and trying to collect many sizes of circular containers, I happened across this The Pi Hoop in the ETA/Cuisenaire catalog.  Since I order all of the math supplies for my school, I thought, “Wow! At only $4.95 I could order a whole class set”.  So I did.  When the hoops arrived I was excited since this alleviated having to find multiple containers to teach the discovery pi lesson.  On showing them to some teachers at a common planning meeting, I was dismayed to find that the cheap plastic cracked when trying to fold down the ruler part that creates the radius of different circles.  If you are gentle with the pi hoops, the concept of the hoop is great because it allows for a discovery lesson–however if an adult was able easily to break the plastic, imagine a class full of kids with the pi hoops in hand.  In my opinion, save your money–they may come out with a sturdier version later on.  Collect containers for now.  An assortment of containers most likely will engage your students more than a plastic hoop anyway.