The Champ won the Guinness Book of World Records award for the longest flight for a paper airplane, (27.6 seconds), in 1998. It was designed by Ken Blackburn. All you will need to make one is a sheet of paper 81/2" X 11", a ruler, and a pencil or something with which to make a mark. It is a little difficult to fold. It would probably appear in the advanced section of a book of paper airplanes. So be patient if it does not all go perfectly well on the first attempt.
NOTE: I have just posted diagrams for Nick Robinson's Memphis Belle at the link below:
Make a mark 2" from each side at the top of the paper, then make two more marks 1/2" above the bottom edge of the paper on each side.
Make valley folds as shown.
Make a valley fold approximately 1/2 inch from the top. Make sure it is a crisp crease. Make eight such folds, making sure they are tight and clean.
Turn the model over.
Valley fold the model in half. Make sure the fold is crisp.
Fold the wings down, making your creases parallel to the center fold, and approximately 1" above it.