  We consider Frobenius objects in the category Span, where the objects are
sets and the morphisms are isomorphism classes of spans of sets. We show that
such structures are in correspondence with data that can be characterized in
terms of simplicial sets. An interesting class of examples comes from
groupoids.
  Our primary motivation is that Span can be viewed as a set-theoretic model
for the symplectic category, and thus Frobenius objects in Span provide
set-theoretic models for classical topological field theories. The paper
includes an explanation of this relationship.
