Herbert S. Wilf, in his book Generatingfunctionolgy, uses cards as a great way to teach combinatorics. cards.tex is a LaTeX package that allows to create such cards in an easy way.
Here is an example followed by the self-explanatory LaTeX code.
% First row
\Card[0.6]{n}{S}{ Picture } \Deck{n}{S}{2}{ Picture } \Deck{n}{S}{5}{ \Rabbit } \Deck{n}{S}{a}{ Picture }
% Second row
\Card{n}{S}{ \Connected[0.7]{3} } \Card{n}{S}{ \Connected[0.7]{n} } \Card{n}{S}{\Cycle[0.7]{ undirected}{3} } \Card{n}{S}{ \Cycle[0.7]{}{n} }
In this section, using cards.tex, we produce some cheat sheets of important topics contained in Wilf's book.
The LaTeX code to produce this table is contained in Resources/Card Structures.tex.
The LaTeX code to produce this table is contained in Resources/The Main Counting Theorems.tex.
The LaTeX code to produce this table is contained in Resources/The Exponential Families.tex.