After Illusions Come the Impossible
Last week's focus was a contest involving the creation of visual illusions, many of which create an aura of the mathematically impossible. Thus, it is only fitting to continue on this theme with a recommendation of a neat web site that focuses on impossible figures, which are closely connected to geometrical thinking.
The Impossible World is run by Vlad Alexeev as a hobby, and offers both an English and a Russian version. Without question, it is a great resource for mathematics teachers and students.
Consider these options:
What more could a mathematics teacher or student want (or have time for)...as the Impossible World seems to cover the impossible!