The project method became a famous teaching method when William Heard Kilpatrick published his article "Project Method" in 1918. The key idea in Kilpatrick's project method is to try to explain how pupils learn things when they work in projects toward different common objects. The same idea of pupils learning by work or action in an environment with objects also belongs to John Dewey's problem-solving method. Are Kilpatrick's project method and Dewey's problem-solving method the same thing? The aim of this article is to analyze and prove that Kilpatrick's project method differs radically from Dewey's problem-solving method.