This is not a treatise on optics or the index of refraction. It is merely a demonstration that will surprise and engage many of your students. We have all put a pencil in a beaker of water and observed how it appears to bend.1 Not so much fun or engaging, is it? Why not illustrate this optical effect by taking your students spearfishing? Simulated spearfishing, to avoid the financial and legal ramifications.

Topics
Composite materials, Optical effects, Optical properties, Visual system, Chemical elements, Educational aids, Educational assessment
1.
R. A.
 
Serway
 and
C.
 
Vuille
,
College Physics
, 9th ed. (
Brooks/Cole
,
Boston, MA
,
2012
), pp.
783
and 803.
Google Scholar
 
© 2014 American Association of Physics Teachers.
2014
American Association of Physics Teachers
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