Optical illusions

Which figure is the tallest? (They all are exactly the same.)

NIEHS Kids

Focus on the dot in the center and move your head forward and back.

NIEHS Kids

Try to count the black dots. Go ahead. Try.

NIEHS Kids

These lines are horizontal. Believe it or not they do not slope.

NIEHS Kids

Try to count the elephant legs.

NIEHS Kids

Focus on the black dot. Keep staring. The gray will appear to shrink.

NIEHS Kids

Is this a rabbit or a duck?

NIEHS Kids