Mission US, an NEH-funded free online game for students in grades five through eight, has won a gold medal at the Serious Play Conference which took place in Redmond, Washington, in August. A panel of experts selected 18 serious games for recognition. This year’s entries included international submissions from Canada, Spain, India, Singapore, the Netherlands, and Macedonia. The Serious Play Conference features the leading thinkers, consultants, authors and analysts in the serious games industry as well as project directors already creating games for education, corporate and military training, healthcare, and nonprofits. Mission US, created by WNET New York in collaboration with historians from the American Social History Project at CUNY, has received wide acclaim by educators since its release in 2010. Through immersive multimedia games, Mission US engages young people in examining five crucial historical moments in the shaping of American ideals and institutions. In each "mission," the player assumes the role of a young person of the time, navigates historical settings, investigates primary documents, and experiences multiple perspectives on events. The first program, “For Crown or Colony?” set in colonial Boston in the weeks leading up to the Boston Massacre, has reached more than 9,700 teachers nationwide and has had a measurable impact on student learning. In 2011, the Education Development Center conducted a major research study that examined the use of Mission US by 1,118 seventh and eighth graders in 50 schools nationwide and reported significant gains in student comprehension of American history and the historical process. WNET New York received a production grant in 2010 to create Mission US.