This papercraft is Snoopy as the World War I Flying Ace, one of the many fantasy identities that Snoopy adopted during the fifty year run of the Peanuts comic strip, the papercraft was created by alf03.
In the early years of the strip, Snoopy would pretend to be other animals, such as a vulture, a boa constrictor or a piranha. As his character developed, Snoopy's imaginary life became more complicated. Many strips would focus on Snoopy pretending to be a lawyer or the student "Joe Cool." However, the World War I Flying Ace would be one of Snoopy's most popular and enduring alternate identities. More information of the World War I Flying Ace at wikia.
You can download the papercraft template here: Peanuts - Snoopy as the World War I Flying Ace Free Papercraft Download [and here]