Seems when M. C. Escher created his famous lithograph Ascending
and Descending (all the way back in 1960.), he didn’t have a
slightest clew how many people will get inspired by this
exceptional deceiving work! Just look how cute R. Watson’s
escher-inspired Lego Penrose turned out to be! But what I also
think, is that it couldn’t hurt encouraging your little toddlers
to try and construct something similar on their own! Not only
will you motivate them to “mathematically” analyze the 3D space,
they will also learn the beauty behind optical illusions, and
educate themselves while doing it! When Escher chose to
construct this deception, he placed the staircase on the roof of
a building and structured the building to convey an impression
of conformity to strong (but inconsistent) vanishing points. He
has the right vanishing point higher than the left one.