Treasure Hunters: All-American Adventure. (Treasure Hunters 6), Paperback/James Patterson

The USA is in danger...and only the Kidds can find the treasure that will save it!Bick, Beck, Storm and Tommy are stuck in Washington, D.C. But everything changes when the Kidds uncover a dastardly conspiracy: a fake Bill of Rights!Now they're crisscrossing the country in a race to prove the document is a forgery.