Sphere Fractions

Teaching fractions with spheres. Put together your own sphere and see what fractions you come up with! They can spin around in the holder and let you add and remove them as you see fit
My first upload to Thingiverse, hope everything comes out ok and sits the right way on the build platform. I hope you like it, would love to hear your feedback in the comments.
Edit:
11/14/13 ~ I've updated the .stl files to mm units (and exported as mm units, don't know why that isn't automatic in Autodesk Inventor) I hope all the files should work now. Will check back tomorrow.