Not a bad quiz, but it's a little ambiguous what you're looking for in some cases. Instead of triangle, those shapes are called "simplexes" so a 1-simplex is a point, a 2-simplex is a triangle, a 3-simplex is a tetrahedron. You should accept 5-cell as an alternate for pentachoron. You should also accept 8-cell and octochoron for tesseract.
Also to prevent ambiguity, the point, line, cube, tesseract series are called measure polytopes.
For the point, circle, sphere series, the proper term is 1-sphere, 2-sphere etc. You could use the term 1-ball, 2-ball etc to avoid using the word sphere (since it's an answer). This not technically accurate, but most people should get it from the clue. Unfortunately this is still not correct, because the progression is incorrect. A 0-sphere is not a singple point, but a pair of points containing a line segment. A 1-sphere is a circle, and a 2-sphere a sphere. A 3-sphere is a hypersphere, for which you should accept "glome" as an alternate.
You could also include the cross polytopes, which is the progression point, line, square (diamond), octohedron, hexadecachoron (16-cell). |
Periodic Table 
The Nine Planets 
Digits of Pi
